Bob Jones - Science 4

•cience

Cover Photo Credits:

Suzanne R. Altizer (large)NOAA (top inset)Unusual Films (bottom inset)

Consultantsfrom the administration.faculty, and staff of Bob Jones University

James R. Davis, M.A., Elementary Project Director, University PressWalter G. Fremont, Ed.D., Dean Emeritus of the School of EducationMelva M. Heintz, M.A., Elementary School PrincipalJanice A. Joss, M.A.T., Professor of Reading, School of EducationPhilip D. Smith, Ed.D., Provost

Note:The fact that materials produced by other publishers may be referred to in this volume does not constitute anendorsement of the content or theological position of materials produced by such publishers. Any referencesand ancillary materials are listed as an aid to the student or the teacher and in an attempt to maintain the acceptedacademic standards of the publishing industry.

SCIENCE 4 Home Teacher's Edition

Authors of Classroom EditionTeresa R. BarnettKimberly A. PascoeDawn L. WatkinsGail H. Yost

Author of Home Teacher's EditionDebra White

Editors of Home Teacher's EditionCarolyn CooperGreg Kuzmic

© 1991, 1995 Bob Jones University PressGreenville, South Carolina 29614

Printed in the United States of AmericaAll rights reserved

ISBN 978-0-89084-569-1

15 14 13

ContentsIntroduction . . . . . . . . . . . . . . . . . . . . . . . . . .Suggested Daily Schedule . . . . . . . . . . . . . . . . . . .Summary of Correlated Skills and Instructional MaterialsGeneral Lesson Plan FormatInstructional MaterialsLesson Plans

History of the Moon .Insects, Arachnids, and Myriapods .Electricity .Plants .Length, Area, and Volume .Digestion .The Moon's Structure and MotionsAnimal Defenses .Light ..Machines .Trees .How the Earth's Crust Wears Down.

SupplementConcepts .Materials List. . . .Bible Action TruthsBible Promises . . .

IVV

VIXIVXV

. 119496891108123143159179195209

231234239241

-/Science ""\

~especially writtenfor the home setting r?®- ~or Christian SchooIs®.J

a program designed to teach science skills by-

1 Developing a knowledge of God• Creation tells us about God (Psalm 19:1; Romans

1:20).• By studying the universe, your student can seeillustrations of God's wisdom, omnipotence, sov-ereignty' and benevolence.

2 Encouraging Christian growth• Your student learns discipline in his attitude andin his fulfilling of responsibilities.

• He should be prepared to evaluate and reject "sci-ence falsely so-called." In certain ways, the studyof science can do more for him spiritually than thestudy of most other subjects.

3 Promoting scientific knowledge, skills, and attitudesin order to identify and to solve science-relatedproblems

• Short statements of scientific knowledge are givenfor each lesson.

• The practical experiences which involve action("hands-on," or "learning-by-doing") activitiesuse process skills such as classifying, measuring,predicting, and experimenting.

• Your student will develop a positive attitude aboutscience by being an active participant.

4 Focusing on the inductive approach to teaching• This method of teaching enables you, the teacher,to stimulate your student to learn through obser-vations, experiments, questions, and discussions.

• Using any of these methods, you lead your studentto take what he knows and discovers in applyinglogical reasoning to form general principles.

IV

5 Providing activities to instill interest in science• Each lesson begins with an activity to stimulateyour student's interest in science.

• As much as possible the activities are homespun,using items that may be found at home or in yourlocal community.

6 Evaluating scientific knowledge and skills• Each lesson includes an activity that will indicatewhether your student has grasped the scientificknowledge and skills.

7 Furnishing you with a flexible schedule• The units may be rearranged to accommodate yourfamily schedule and/or your seasonal teachingschedule.

• The number of lessons taught each week may bevaried according to your schedule and subjectmatter.

• The same lessons usually may be taught to morethan one student in grades 2-5 depending uponeach student's level of understanding.

• All the activities may be done with more than onestudent. Information may be obtained from addi-tional sources for your younger or older childrento meet their individual learning needs.

8 Including Family Times• These lessons have appealing activities to exciteyour student about the next science lesson.

• These activities may involve the whole family orjust you and your child.

Suggested Daily Schedulefor Home Education

Grade 1First Grade English Skills . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60-70 min.

Listening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5-10 min.Phonics and Structural Analysis 15-20 min.Handwriting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5-10 min.Word Work 10-15 min.Grammar and Composition 10-15 min.

Spelling 15-20 min.Bible 20-30 min.Reading 20-30 min.Heritage/Science 20-30 min.Math 15-25 min.Music/Art 15-25 min.

Grades 2-6Bible 20-25 min.Writing and Grammar 15-30 min.Reading 20-30 min.Math 20-30 min.Spelling 15-25 min.Handwriting 5-10 min.Heritage/Science 20-30 min.Music/Art 15-25 min.

Suggested Daily Schedule v

vi

SUMMARY OF CORRELATED SKILLSAND INSTRUCTIONAL MATERIALS

1

Lesson Suggested LessonChapter and Lessons numbers Teaching pages

Days

History of the MoonBreak-Away Bread FT* 1 1 2Theories About the Moon's Origin 1 1 3-6

More Theories About the Moon's Origin 2 2 7-10

The Age of the Moon 3 2 11-13

The Purpose of the Moon 4 1 14-17

Insects, Arachnids, and MyriapodsInsect Orders 5 1 20-23Dragonflies, Aphids, and True Bugs 6 1 24-27

Finding Out About Insects FT 7 1 28Butterflies, Beetles, and Flies 7 2 29-32Finding Out About Ants FT 8 1 33-34Bees and Ants 8 3 35-39Identifying Insects 9 2 40-44

Arachnids and Myriapods 10 2 45-48

ElectricityMaking Electricity Work 11 1 50-53

Static Electricity 12 2 54-58

Looking Ahead FT 13 1 59Electricity in Motion 13 2 60-63Electricity and Magnetism 14 2 64-67

2

3

* Family Time

SCIENCE 4 HTE

Text Notebook Bible Action Truths

pages pages Bible Promises Process SkillsIReflections of God

2-4 BAT: 8b Faith in the power of observingthe Word of God; BiblePromise: I. God as Master/God creates

5-8 BAT: 8b Faith in the power of predictingthe Word of God

9-11 BATs: 1b Repentance and predictingfaith, 2c Faithfulness

11-16 1 BAT: 7f Praise; Bible Promise: observing, using space-timeH. God as Father/God relationshipscreates, God sustains

18-20 /God creates predicting21-23 Bible Promise: I. God as inferring, using numbers

Master/God creates34

24-27 2-3 /God creates classifying30

28-32 4-7 BAT: 2e Work observing33-34 8-11 Bible Promise: I. God as classifying

Master35-38 /God creates observing, classifying

40-42 12 Bible Promise: I. God as observingMaster/God is all-powerful

43-47 13-14 Bible Promise: I. God as observingMaster/God is all-powerful

5848-50 15 observing51-54 16 /God creates inferring, predicting

Skills and Materials vii

viii

4


Days

PlantsFungi 15 2 69-73Algae, Mosses, and Liverworts 16 2 74-76

Ferns 17 1 77-79Nature Walk FT 18 1 80Conifers 18 2 81-85Flowering Plants 19 2 86-89

Length, Area, and VolumeLength 20 2 92-94

Triathlon FT 21 1 95-96Metrics 21 1 97-99

Area 22 1 100-103

Volume 23 1 104-7

DigestionThe Mouth 24 1 109-11The Throat 25 1 112-15The Stomach 26 1 116-18

The Intestines 27 1 119-22

5

6

SCIENCE 4 HTE



56-59 17-18 /God creates observing, classifying60-61 19 Bible Promise: I. God as observing, classifying

Master62-64 20 /God creates classifying

65-69 21 /God creates observing, classifying70-76 22 Bible Promise: I. God as observing, classifying

Master

78-80 23 BAT: 8a Faith in God's measuring, using numberspromises

2481-82 24-25 classifying, measuring, using

numbers83-85 26 BATs: 2e Work, 5a Love, measuring, using space-time

5e Friendliness, 7c Praise, relationships7d Contentment

86-90 27-28 using numbers

92-94 29 /God creates observing95-98 30 observing99-101 BATs: 6c Spirit-filled, 7d observing

Contentment102-6 BATs: 1c Separation from the observing, predicting

world, 3b Mind, 3d Body asa temple

Skills and Materials IX

to

x

7


Days

The Moon's Structure and MotionsMaking Play Dough FT 28 1 124The Moon's Features 28 1 125-28Model of the Moon's Surface FT 29 1 129Description of the Moon 29 2 130-33

The Moon's Motions 30 2 134-36

Lunar and Solar Eclipse FT 31 1 137-38The Moon's Phases 31 2 139-41

Animal DefensesCamouflage 32 1 144-47

Weapons, Protective Coverings, and 33 1 148-51Special Defenses

Animal Defense Game FT 34 1 152-53Tactics 34 2 154-57

LightThe Characteristics of Light 35 3 160-63

The Human Eye 36 2 164-67Color 37 3 168-71

Reflection 38 1 172-74

Lasers 39 1 175-77

MachinesInclined Planes 40 2 180-83Pulleys, Wheels, and Axles 41 1 184-87Levers 42 2 188-90Wedges and Screws 43 2 191-94

8

9

SCIENCE 4 HTE

Text Notebook Bible Action TruthsBible Promises Process Skillspages pages

IReflections of God

108-11 31 /God creates observing

112-16 32-33 Bible Promise: I. God as measuring, using numbersMaster/God sustains

117-19 34-35 Bible Promise: I. God as using space-time relationships,Master/God sustains, God inferringcreates

36120-22 36-37 BAT: 7c Praise/God is all- observing

powerful

124-28 38-39 Bible Promise: I. God as observing, classifyingMaster

129-33 40 /God creates observing, classifying

134-38 41 /God creates observing

140-43 42-43 Bible Promise: I. God as observing, classifyingMaster/God creates

144-46 44-45 /God creates observing147-52 46 BAT: 8a Faith in God's predicting, observing

promises153-56 Bible Promise: H. God as observing, inferring

Father/God is all-knowing47 observing

158-62 observing, measuring163-65 48 observing, measuring166-67 49-50 observing, measuring168-70 51-52 /God is holy observing, classifying

Skills and Materials Xl

11

12

xii


Days

TreesIdentifying Leaves Part 1 44 2 196-99Identifying Leaves Part 2 45 1 200-202

Identifying Trees 46 2 203-5

Adopt-a- Tree 47 1 206-8

How Earth's Crust Wears DownFinding Out About Frozen Water FT 48 1 210Weathering 48 3 211-15The Earth and Its Land FT 49 1 216Mass-wasting and Erosion 49 3 217-19

Water Erosion 50 2 220-24Preventing Erosion 51 2 225-28

SCIENCE 4 HTE



172-75 /God creates observing, classifying176-77 53 /God creates observing, classifying,

communicating178-80, 54 Bible Promise: E. Christ as observing, classifying182 Sacrifice/God is all-powerful181 55-56 Bible Promise: H. God as observing

Father

184-88 57 observing, predicting

188-91 BAT: 1a Understanding Jesus observing, predictingChrist/God is all-powerful

192-97 58 /God sustains observing198- 59-61 BATs: 2c Responsibility, 3d observing, predicting201 Body as a temple, 8a Faith

in God's promises, 8b Faithin the power of the Word ofGod; Bible Promise: I. Godas Master/God sustains

Skills and Materials xiii

General Lesson PlanFormat

SCIENCE4 for Christian Schools® is a developmen-tal science program. In the hands of a skillful teacher,these materials can be used to teach not only scientificliteracy but also a knowledge of God and Christiancharacter. The lessons are designed to fit your sched-uling needs and should be arranged to accommodateyour student and your family's schedule. The recom-mended time for teaching science is twenty to thirtyminutes per lesson. Many of the lessons may be taughtover a period of several days. One day could be devotedto the preparation and the set-up. Another day could begiven to the activities of the lesson, and a third daymight be used for reading, discussion, and evaluationof the lesson. If you desire to shorten the actual teachingtime, you could prepare the materials ahead of time andteach the lesson in one day. These are suggested pacesfor accomplishing the lessons.

There is a uniform format for the lesson plans. Eachlesson contains three major divisions: Preview, Lesson,and For Your Information. The following is an overviewof each division.

PreviewThe Preview contains the main lesson objectives and

the materials needed for each lesson. The Objectives arestatements describing the desired outcome of instructionin terms of student behavior. It is important that youread the objectives and keep them in mind as you planand teach the lesson.

The Materials is a list of items to be obtained orprepared. They are listed for your convenience andshould be taken into consideration before the day of thelesson. You will find some materials marked with an *.These items need to be purchased or prepared beforethe presentation of the lesson. The materials markedwith a t may be purchased from Bob Jones UniversityPress.

Occasionally this section will also contain Notes,which will give you helpful hints for teaching the lesson.

LessonThe section Introducing the Lesson suggests an ac-

tivity to begin the lesson. The activity will stimulateyour student's interest in science and the lesson thatfollows.

xiv

The section Teaching the Lesson contains a textactivity. Several questions are given to stimulate yourstudent's interest in what he is going to read silently.There are questions and statements to help you guide adiscussion with your student about what he read.

Evaluating the Lesson is a section that gives activ-ities to evaluate, not test, the student's grasp of thematerial presented.

EnrichmentThis is an optional section found in some lessons.

It contains experiments or games that your student cando independently.

For Your InformationThis section provides you, the teacher, with extra

information to help you expand your scientific knowl-edge. It is not necessary to understand or even read theinformation in this section in order to teach the lesson.Your student does not need to become acquainted withthe information in this section unless he shows specialinterest in the topic.

SCIENCE 4 HTE

Instructional MaterialsTeacher Materials

SCIENCE4 for Christian Schools® Home Teacher'sEdition This manual includes all of the lesson plansfor teaching fourth-grade science. It includes a sectionon General Lesson Plan Format which gives an over-view of each segment of the lesson plan. In the Supple-ment there is a list of concepts which are given by lessonnumber. The concepts are short statements of scientificknowledge which your student will learn about in thatlesson,SCIENCE4 Home Teacher Packet This packet con-tains prepared visuals, charts, and games to aid in teach-ing the lessons. The numbers at the bottom of each pageindicate both the grade and the page number (e.g., 4-10means grade 4, page 10). (NOTE: In the Home Teach-er's Edition they will be referred to by page numberonly.)Write It Flip Chart This flip chart is a tablet of blankpaper that you can use instead of a chalkboard or chartpaper.Science supplies Refer to the materials section in theSupplement of this book for a complete list of itemsneeded to teach each lesson.

Student MaterialsText SCIENCE4 for Christian Schools® is a hardcoverfour-color text containing a variety of developmentalSUbtopics built around seven major topics: LivingThings, Human Body, Earth, Space, Matter, Energy,and Motion.Notebook SCIENCE4 Notebook Packet is a consumablecompanion tool for the text. It contains sixty-one pagesthat are used primarily for recording scientific data.These recording activities will help your student under-stand the importance of keeping scientific records. Thenotebook will also save time for the teacher. The pagesare designed to be used in a three-ring notebook binder.Miscellaneous supplies Your student will need stan-dard supplies: crayons or felt-tip pens, pencils, scissors,glue, etc.

Instructional Materials

Human Body

Earth

Matter

Space

Living Things

Energy

Motion

xv

CHAPTER

1History of the Moon

~

Lessons 1-4

gHistory of theMoon

Chapter 1: Introduction

This chapter contrasts the evolutionary theories withthe Biblical account of the beginning of the moon. Thelessons provide activities and demonstrations in whichyour student will examine the attempts of unsaved men toexplain how things happened without taking God into ac-count. Your student will learn to tell the difference betweenwhat can be observed by the senses and what must beaccepted by faith.

MaterialsThe following items must be obtained or prepared be-

fore the presentation of the lesson. These items are des-ignated with an * in the materials list in each lesson andin the Supplement. For further information see the indi-vidual lessons.

* 3 cans refrigerated biscuit dough (Family Time 1)* SCIENCE 4 Home Teacher Packett (Lesson 2)* Write It flip chart] (Lesson 3)* A globe] (Lesson 4)* SCIENCE 4 Notebook Packett (Lesson 4)* Three-ring binder (Lesson 4)

FamilyTime 1

Break-AwayBread

Instructions -----Family Time has appealing activitiesto excite your child about the next sci-ence lesson. These activities do notneed to be handled during your teach-ing time. They can involve the wholefamily or just you and your child.

Prepare a loaf of "Break-Away Bread." Tell yourchild he will be making an unusual type of bread-eachpiece is broken off instead of sliced. Guide him as hemakes the bread using the following instructions:

Materials

Be sure to save a wrapper from one ofthe cans of refrigerated biscuits. It willbe used in the first lesson.

Have available:• 3 cans refrigerated biscuit dough.*• + cup melted margarine.

3• "4 cup granulated sugar.• 2 teaspoons cinnamon.

Lightly grease a bundt pan. Cut each biscuit in halfand dip each piece into the melted margarine. Roll thepieces in the cinnamon-sugar mixture and arrange themin layers (like bricks) in the greased pan.

Bake at 350 degrees for 35 minutes.When the bread is done, invert it onto a plate imme-

diately. Save the bread for the science lesson tomorrow.

2 SCIENCE 4 HTE

Lesson 1Theories Aboutthe Moon's

OriginText, pages 2-4

PreviewObjectives

Given proper instruction, your student will be able todo the following:

• Describe an object by using the five senses.• Discriminate between things that can and cannot be

observed.• Describe the difference between the Creation Model

and the Evolution Model.

MaterialsHave available:

• 1 napkin.• 1 dampened towel (optional).• 1 loaf of "Break-Away Bread" (prepared in Family

Time 1).• 1 wrapper from a can of refrigerated biscuits.

NotesIn this first lesson you will have the opportunity to

explain that science is limited. Since science is learnedonly through the senses, science must be limited. That is,science can be wrong, and it can also change. In fact, thereare many things that science cannot do. For example, sincescience is based on what can be observed, it cannot dealwith beginnings (for example, the beginning of the earth,the moon, the solar system, the universe, or life). Whatsomeone believes about those origins is by faith, notscience.

Chapter 1: Lesson 1

"And God made t\\'o great lights; the greater light to rulethe dav, and the lesser light to rule the night: he made thestars also." Genesis 1:16

The Moon's BeginningScience can be defined as "information gained by using

our senses." Faith means "holding beliefs without seeing.hearing, tasting, smelling, or touching the proof of them."

When the moon came into being, were there any peoplethere to get facts through their senses? Then do all ourideas about where the moon came from rest on science orfaith? What anyone believes about the beginning of thingsrests on faith, not science. Hebrews 11:3 says that "Through[aith we understand that the worlds were framed by theword of God."

2

LessonIntroducing the Lesson

Each lesson begins with an activity tostimulate your child's interest inscience.

Introduce an activity dealing with the senses. Set theloaf of "Break-Away Bread" and a napkin on a table.Explain to your student that he is going to describe thisbread like a scientist. Ask him which senses tell himsomething about the bread. (sight, touch, smell, taste)Direct the activity. Instruct your student to use hissenses of sight, touch, and smell (saving taste until hehas used the other three senses) to describe the bread.Ask him to describe how the bread looks, feels, andsmells. Guide him in using specific words, such asbrown, crusty, sticky, lumpy, and spicy rather than tasty,delicious, or yummy. Then invite him to eat the breadand to describe its taste. Emphasize the use of specificwords, such as sweet, chewy, or crunchy, for this sensealso. (NOTE: At this point you may want to provide adampened towel for cleanup.)

3

Theories on the Moon's OriginPeople who accept the Bible believe that God made

everything. They call God's description of how things beganthe Creation Model. Those who disregard the Bible believeinstead that everything got here by itself. They call thisdescription of how things began the Evolution Model.Evolutionists try to guess what events caused things like themoon. Following are three guesses made by evolutionistsabout how the moon began.

The Break-Away TheorySome scientists believe that the earth was once like a

rolling, boiling ball of lava such as volcanoes spit out. Asthe sun's gravity pulled on the earth, a large lump of softrock formed on one side of it. Because the earth wasspinning fast, this lump broke away and shattered into tinypieces. Then the pieces pulled back together to make themoon. The "hole" left in the earth, they say, became thePacific Ocean.

3

Continue the activity. After discussing his descriptionof the bread, ask your student what ingredients wereused to make the refrigerated biscuits, Ask him why heis having trouble explaining what ingredients were used,(He was not present during the process, and he hasnever read about it or seen it.) Tell him he can read thelabel on the wrapper of the refrigerated biscuits to seewhat ingredients were used. If he trusts the companythat made the biscuits, he will probably believe what hereads as the ingredients that were used.Conclude the activity. Allow your student to read thewrapper to see what ingredients were used to make thebiscuits, Point out the similarities and differences be-tween his account and what he read from the wrapper.Explain that there are some similarities between thisactivity and the science lesson for today.

Teaching the LessonDirect a text activity on pages 2-4. Use the followingquestions to initiate your student's interest in what heis going to read,1. What is faith?2, What is the Creation Model?3, What is the Evolution Model?

4

See if you can find any problems with (hi, theory. Lookfor a moment at the chart. The column labeled dens it)'shows how (he mass of one cubic foot of earth compares toone cubic foot of the moon. Is the earth's density the sameas the moon's density? Shouldn't they be the same if themoon came from the earth? Check the other columns. Dothe earth and (he moon have the same rocks and minerals')What do you think about this Break-Away 'Theory? Does itseem that the moon could have corne from the earth?

EARTH MOONDensity 5.52 gms/cm3 3,34 gms/cm3

Igneous Rocks: mostly granite no granite

MineralsArmalcolite not found on found on moon

earthTranquillityite not found on found on moon

earthPyroxferroite not found on found on moon

earth

Asking your child questions will en-courage him to develop his own ideas,

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read,1. What is faith? (Faith means holding beliefs without

seeing, hearing, tasting, smelling, or touching theproof of them.)

2, What is science? (Science is information gained byusing the senses.)

3. Which part of the bread activity was scientific, andwhich part of the bread activity was based on faith?(Your student's description of the bread and thecon's description of the ingredients in the biscuitswere scientific; your student's acceptance of theingredients in the biscuits was based on faith.)Explain that what he chooses to believe about theingredients in the biscuits and even about whomade them is based on faith because he was notthere to observe them being made, Not until theperson actually sees the whole process of the bis-cuits being made can his description of it be con-sidered scientific.

SCIENCE 4 HTE

4. What science do you know about the moon? If hedoes not have any ideas, ask him questions suchas: What shape is it? Where is it located? Who cansee the moon? (Answers will vary. It is shaped likea ball; it is in the sky; it can be seen from theearth.) Point out that there are some things that aperson accepts as science because another personhas observed them and reported them to others.Because of accepted reports from astronauts whovisited the moon and scientists who studied themoon rocks, your student can also say that heknows some science about the surface of the moonand the rocks found on the moon.

5. What science do you know about the beginning ofthe moon? (none)

6. Who would know any science about the beginningof the moon? (only the one who made the moonand someone who observed the creation of themoon)

7. Did anyone observe the moon being made? (no)8. What source do Christians have of the beginning

of the moon? (the Biblical account of creation writ-ten by the Creator Himself) (BAT: 8b Faith in thepower of the Word of God; Bible Promise: 1. Godas Master)

9. What is the Creation Model? (The Creation Modelis God's description of how everything began.)

10. What is the Evolution Model? (The EvolutionModel is man's description of how things mighthave begun by themselves.)

If your child does not know the differ-ence between a fact and a theory, youmay find the following definitionshelpful. Afact is something that a per-son knows from his observations; itcan be proved. A theory is an idea thata person comes up with by studyingthe facts; it is an opinion. If a theoryis tested and retested and produces thesame results, that theory may becomea law of science.

Conclude the discussion. Direct your student's atten-tion to the figure on page 4 as you discuss the Break-Away Theory. Ask him to answer the questions in thestudent text. (The earth is more dense than the moon,according to the measurements in grams per cubic cen-timeter. The igneous rocks on the earth are mostly gran-ite, whereas moon rocks have no granite. There arethree minerals on the moon that are not found on theearth. These differences do seem to indicate that themoon did not break away from the earth.)

Chapter 1: Lesson 1

Besides having no granite in its igne-ous crust, the moon also has no mois-ture nor indication of a former watersupply.

Explain that in naming one of the lunar materials,Armalcolite, scientists combined parts of the names ofthe Apollo 11 team-Armstrong, Aldrin, and Collins.

Show your student the rest of the "Break-AwayBread." Review the Break-Away Theory and its flawsby asking him questions. Was the piece of bread thathe broke from the loaf the same type of bread as therest of the loaf? (yes) Did he see, feel, smell, and tastethe same ingredients baked as you did? (yes) Would themoon contain the same ingredients as the earth if themoon were taken from the earth? (yes) Does the mooncontain the same elements as the earth? (no)

Evaluating the LessonIntroduce the evaluation. Ask your student to list thesenses with which a person can observe. (sight, hearing,touch, smell, taste) Tell your student that you are goingto read to him a list of things that he can or cannotobserve. If it can be observed, he should tell you whatsense or senses he would use to observe it.Direct the evaluation. Read the following phrases oneat a time to your student.1. a bicycle tire (can observe-sight, touch, smell)2. the surface of the moon (can observe-sight)3. the center of the moon (cannot observe)4. the wind (can observe-touch, hearing)5. a fish in a fish tank (can observe-sight)6. a plate of cookies (can observe-sight, touch, smell,

taste)7. a building being built (can observe-sight, hearing,

smell, touch)

5

For Your Information

This is extra information for you. It isnot necessary to understand or even toread the information in this section inorder to teach the lesson. Your childdoes not need to become acquaintedwith the information in this section un-less he shows special interest in thetopic.

The differences between lunar rocks and terrestrialrocks discredit the theory that the moon spun off fromthe earth. However, a person must keep in mind that atotal of 382 kilograms (840 pounds) of lunar rocks andsoil from six different locations was transported to theearth by six Apollo mission teams. Although that is alarge amount of rock, does it give an accurate represen-tation of the moon's geology? Most scientists agree thatit does. The differences between lunar rocks and terres-trial rocks are obvious to all the scientists that wereinvolved in the Apollo missions. They are convincedthat the earth and the moon were never part of the sameplanet. Some scientists, however, continue to link theearth with the origin of the moon.

6 SCIENCE 4 HTE

Lesson 2More Theories

About theMoon's Origin

Text, pages 5-8

PreviewObjectives


• Demonstrate the difficulties of the Capture Theory.• Describe the Condensation Theory.


• 1 soccer ball or basketball.• 1 container of baby powder.• 1 SCIENCE 4 Home Teacher Packet, pp. 1-4.*t

Prepare:• The Moon Memory Game found in the Home Teach-er Packet. Cut each of the four pages into four pieces.


Conduct a demonstration of the Capture Theory.Take your student to the back yard. Explain that hisbody represents the earth and that the center of the"earth" is the middle of his body. Ask him to extendboth arms. His arms represent the earth's gravity, whichis effective only as far as his arms can reach.

Tell him that you are going to toss him a ball, rep-resenting the moon. Wherever the ball (moon) goes, he(the earth) should try to grab it with his hands, makingsure that he does not move from the place that he isstanding.

Toss the ball a few times from different directionsand comment on what happens. A successful catch maynot occur on the first tries.

Once he catches the ball, add the spinning motionof the earth to the demonstration. Make the "earth"

Chapter 1: Lesson 2

The Capture TheoryWhat do you think of when you hear the word capture?

Gangsters or pirates? To "capture" usually means to seizesomeone or something from another place. Those whobelieve the Capture Theory think that the moon once hadits own path around the sun like the nine planets. But whenthe earth's path came close to the moon's path, the earthcaptured the moon with its pull of gravity.

This theory also has some problems. One problem hasto do with which has more "stuff," the earth or the sun. Themore "stuff" something is made of. the more pull of gravityit has. The sun has 333,400 times more material than theearth. So which has the greater pull of gravity? The sundoes. If the moon was once on its own path around the suo,then how could the earth (distances remaining the same)capture the moon away from the sun'! Could some bigaccident have helped the earth capture the moon'? The solarsystem is so orderly that such an accident does not seempossible.

5

spin counterclockwise by asking your student to turn ina circle, still extending his hands. Toss the ball (themoon) as you did before, encouraging him (the earth)to try to grab it. Discuss what happens.Discuss the Capture Theory. Point out that this dem-onstration shows a theory called the" Capture Theory. "According to that theory, the moon once orbited thesun, as other planets do. One day, the moon passed alittle closer than usual to the earth, was caught by theearth's gravity, and started moving in an orbit aroundthe earth rather than around the sun.Conduct a predicting activity of the CondensationTheory. Back in the house, tell your student that youare going to make a cloud of dust by releasing somebaby powder into the air. Ask him to predict what willhappen to the cloud of dust. (Predictions will vary.) Tellyour student to watch carefully as you make the dustcloud. Hold the baby powder container above your headand at arm's length in front of you. Squeeze the con-tainer lightly a few times, releasing enough powder foryour student to see. Ask him to explain what is happen-ing to the cloud of dust. Tell your student that thisdemonstration of the particles of powder coming to-gether describes another theory that he is going to readabout in his textbook.

7

Another problem with the Capture Theory bas to dowith the speed of the moon. If the moon had been travelingslowly when it came near the earth, it would have crashedinto the earth and broken up into small pieces. If it hadbeen traveling really fast, it would have zoomed off into anew path around the sun. It would have been a rare chanceindeed that the moon was traveling at just the right speedto gel captured in one piece by the earth.

Furthermore. this capture might have caused great heaton earth. Some scientists believe that it would have madeso much heat that pan of the crust would have melted. Butwhen they look at the earth's materials, they find noevidence that anything like that ever happened.

6

Teaching the LessonDirect a text activity on pages 5·8. Use the followingquestions to initiate your student's interest in what heis going to read.1. What are three problems with the Capture Theory?2. What is a problem with the Condensation Theory?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Which has the greater pull of gravity: the sun or

the earth? (The sun, with its greater mass, has amuch greater pull of gravity than the earth.)

2. Could the earth pull something away from thesun's orbit? (no)

3. In relation to the Capture Theory, what is the prob-lem with the speed of the moon? (The moon wouldhave to have been traveling at just the right speedto avoid crashing into the earth or going into anew path around the sun.)

4. The capture would probably have caused great heaton earth. Is there any evidence that such heat everoccurred? (no)

5. Do the earth and the moon have the same rocksand minerals? (No, if the earth and the moonformed from the same cloud of dust and gas as the

8

The Condensation TheoryThe word condense means "to make thicker." What are

scientists who believe this theory thinking? They think that

the earth and the moon were both formed from the samecloud of dust and gas. They assume that the dust and gascondensed, or thickened, to make a solid earth and moon.

You probably see a problem with this theory right away.How did the gas and dust gradually come together" Haveyou ever heard of it happening before'! YOLI have alreadyseen that the earth and moon have different densities anddifferent rocks and minerals. If the earth and the moonformed from the same gas and dust, should they not bemore alike? Do you think this theory is reasonable'?

theory proposes, they should be more alike thanthey are.)

6. Why do you think someone would believe a theorylike one ofthe three you have read about? (Answerwill vary. A belief in any of those theories must bebased on faith in the logic of the theory or on arejection of faith in the God of creation.)

SCIENCE 4 HTE

The Biblical Record of the Moon's OriginThe three theories just discussed are some scientists'

guesses about how the moon began . But Christians do nothave to guess how things began. The Bible not only tells LIS

that God made the lights in the heaven but also that Hemade them out of nothing. The last part of Hebrews 11:3says "that things which arc seen were not made of thingswhich do appear." No material thing existed until Godspoke.

The creation of the moon, like everything else. tookplace immediately. Psalm 33:9 says, "He spake, and it wasdone." The moon sprang into being in an instant. at God'scommand.

8

We suggest that, although Psalm 33:9is included in the student text, you readthis section aloud from the Bible toyour child. Throughout the year, takeevery opportunity to reinforce the factthat the Bible is vital to a Christian'sstudy of science.

Conclude the discussion. Read Psalm 33:6-11. Pointout not only that God spoke the moon into being, butalso that God shows unsaved man's thoughts (counsel)to be foolish and illogical. Ask your student what in-gredients God used in making the moon. (none) En-courage him to compare everything that he reads aboutthe beginning of the world with what God says aboutcreation. God's counsel stands sure forever. (BAT: 8bFaith in the power of the Word of God)

Chapter 1: Lesson 2 9

Figure 2-1

CREATIONThrough faith we understand

that the worlds were framed bv(nc word of God. so that thing..,which are seen were no! made ofthings which do appear.

HEBREWS 11:3

For he spake. and it waxdone: he commandcd.nndit SlOnu f01.,\CREATION

CAPTURETHEORY

BREAK-AWAYTHEORY

Evaluating the LessonIntroduce the Moon Memory Game. Show your stu-dent the pieces for the game. Point out that some piecescontain drawings and others contain words. Discusseach drawing, asking whether it represents the Break-Away Theory, the Capture Theory, or the CondensationTheory of the beginning of the moon. (NOTE: See Fig-ure 2-1.) Then show him that each drawing can bematched with the name of the theory that it illustrates.As you show the Scripture references, ask what wordthey should be matched with. (creation)

You will want to play this game withyour child. He may show the familywhat he has learned about the moon'sorigin by playing it with other familymembers.

Direct the game. Explain that the game pieces shouldbe mixed up and then placed on the floor or a table,face down, in a square of four pieces across and fourpieces down. You will each take a turn trying to pointto two pieces that will match when turned over. If ac?rrect match is made, the pieces should be left right-SIde-up and a point given. The same player may contin-ue to playas long as he makes correct matches. The

10

CAPTURETHEORY

CAPTURETHEORY

CONDENSATIONTHEORY

CONDENSATIONTHEORY

player with more points when all the pieces have beenmatched is the winner.

To use these game pieces after this les-son, you may want to mount them onheavy paper or cover them with clearcontact paper to ensure durability.

For Your InformationScientists have come up with yet another theory

about where the moon came from. The theory proposesthat just after the earth was created, another planet or ahuge asteroid hit the earth. Supposedly, the material thatwas blasted from the earth during the collision drewtogether in space and formed the moon. Scientists donot include what happened to the "hit-and-run" planetor asteroid other than theorizing that it went on its wayafter the crash.

SCIENCE 4 HTE

Lesson 3The Age of the

MoonText, pages 9-11

PreviewObjective


• Describe three evidences of the moon's young age.


• 1 container of baby powder.• 3 sheets of red (or blue) construction paper.• A Write It flip chart.*t


Direct a predicting activity. Tell your student that sci-entists have found that dust settles on the moon veryslowly. Layout the three pieces of construction paperon a table. Hold the container of baby powder about afoot above the paper and squeeze it lightly. Let thepowder settle. Then tell your student that a layer of dustabout as thick as the powder on the paper collects onthe moon in a year. Ask him how long he thinks itwould take for an inch of dust to collect on the moon.(Answers will vary.) Squeeze the powder several timesto demonstrate the accumulation of dust. Tell your stu-dent that the amount of dust that the astronauts foundon the moon shows the moon to be young.

Chapter 1: Lesson 3

The Age of the Moon"Howald is the moon?" This question has puzzled

scientists for centuries. Evolutionists assume that the moonis billions of years old because their model requires greatspans of time for things to happen by chance. Butcreationists believe the moon is much younger, perhapsonly 10,000 years old.

Activity on the MoonOne trait of youth is activity. Many people have

observed signs of activity on the moon, such as streaks oflight flashing and small areas changing color. Such activityis called transient lunar phenomena. Some people havewritten books telling about their observations. If suchchanges arc taking place on the moon today, is the moonmore likely old and dead or young and active?

Teaching the Lesson

The bottom of page 11 beginning withThe Purpose of the Moon will be dis-

~ cussed in Lesson 4.~----1

Direct a text activity on pages 9-11. Use the followingquestions to initiate your student's interest in what heis going to read.1. What name do scientists give to the changes in

light and color on the moon?2. How much dust did the astronauts discover when

they were on the moon?3. Is the moon getting closer to or farther from the

earth each year?Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. What do you think lunar means? (moon; of the

moon)2. Phenomena means "things which the senses detect

but that cannot be explained."3. What do you think transient means? C'changing

or moving" )

11

DustEach year dust from comets and material from the sun

settle onto the earth and moon. On the earth, this dust

finds its way to the oceans. On the moon, it settles in thelow areas. Scientists have figured out how much dust buildsup each year on the moon. If they assume that it has alwaysbeen the same amount each year, then they can calculatehow much there is with the following formula:

Suppose you figured out that .000 I inches of dust gatherson the moon each year. An evolutionist would multiply.0001 inches per year times one billion (1,000,000,000)years. And he would say that the moon had one hundredthousand (100,000) inches of dust' But a creationist wouldmultiply .0001 inches per year times 10,000 years. And hewould say that the moon has one inch of dust. H ow muchdust did the astronauts discover when they were on themoon? They found only a very thin laycr. Docs the moonseem to be old or young?

10

4. Putting all the definitions together, what does thephrase transient lunar phenomena mean? (thingswe can see moving or changing on the moon butcannot explain)

5. Is activity more often a characteristic of youth orage? (youth)

6, What does this first observation about the moonseem to show? (a young moon)

Write the following formula on theWrite It flip chart before discussing thenext question:build-up per year x years = amount of dust

7. Fill in the following numbers in the formula on theflip chart: 0.0001 inch dust a year x 10,000 years= 1 inch of dust. Look at the picture on text page10 of the footprint that an astronaut made on themoon.

8. Do you think that the dust on the moon has beenaccumulating for about 10 thousand years or 1billion years? (10 thousand) You may think that10 thousand years old is very old. One billion yearsis 100 thousand times older.

9. Is the moon getting closer to the earth each year?(no)

12

DistanceAnother reason to believe that the moon is young is its

distance from the earth. Scientists have found that the

moon is gelting farther away from the earth each year.They can measure how much farther away it is getting eachyear. Evolutionists could multiply the distance that themoon is moving away by one billion year, (the age theythink the moon is). This would tell them that the moonshould he farther away than it is. Could the moon he as oldas the Evolution Model require, it to he'!

238.900 mites 0------~m~e~'n~di~sta-n-ce-------

The Purpose of the MoonHave you ever wondered why God made you" Or why

God made anything'! God made you and all things for Hisown glory (1 Chronicles 16:28, Romans 11:36, and [Corin-thians 6:20; 10:31). But how can something like the moonbring glory to God" Read the following verses and seewhether you can find three ways that the moon can"declare the glory of God.""And God said, tel there he lights ill the firmament of theheaven to divide the dayfrom the night; and le! them beforsigns. andfor seasons, andfor days, and years; And leithem he for lights in thefirrnament of the heaven 10 givelight upon the earth: and it was so." Genesis 1;14-15

Do you see that God made the moon and all "lights inthe firn;ament" to be for signs, for seasons, and for lights in

the heaven?

10. Since the moon is closer than evolutionists think itshould be, could the moon be as old as the Evo-lution Model requires it to be? (no)

Conclude the discussion. Guide your student in a dis-cussion of the Evolution and Creation Models of themoon's beginning, Ask him which model accounts morereasonably for the facts that he has about the moon.(Creation Model) Ask him why some people might wantto believe the Evolution Model. (to avoid responsibilityto an all-powerful God) (BAT: 1b Repentance and faith)

Evaluating the LessonDirect a writing activity. Allow your student to pretendto be a scientist in a lunar observatory. He has gathereddata and is now supposed to write a brief article for theobservatory's newsletter, The Crescent. The article'stitle is "New Evidence on the Age of the Moon."

The article can be one to three paragraphs long.Allow him to write to a general audience such as anewspaper writer would, Ask him to be objective andclear in his article.

When he has finished, ask him to underline the mainfacts he has used in his article, Scan the paper, lookingto see that he has the three main proofs of the moon'syouth: transient lunar phenomena, small amount of dust,and short distance from the earth.

SCIENCE 4 HTE

11

At supper or another appropriate time,let your child read to the family thearticle he has written. You may wantto display the article on the refrigeratoror in another prominent place.

For Your InformationThe theories about the causes of transient lunar phe-

nomena are many. Some scientists hold to the idea thatthe flashes of light and color are no more than resultsof bad observing conditions or tricks of the eyes. Othersbelieve them to be effects produced by the sun's ultra-violet rays and charged particles from space. Most at-tribute the phenomena to the hot interior workings ofthe moon. A few propose volcanic eruptions, but thegreat size of some phenomena (one was almost 100miles across) make that theory mostly unworkable. Oth-ers suggest that escaping gases disturb the fine dust ofthe surface and set off lightning effects in the powderyair.

Since reports of transient lunar phenomena began in1725, there have been too many reliable sightings forthe scientific community to disregard them any longer.The only reasonable conclusion that acceptance of thesephenomena allows is that the moon is not, as was be-lieved, cold and dead. To recognize the existence oftransient lunar phenomena is to admit that the moon isan active satellite.


Lesson 4The Purpose of

the MoonText, pages 11-16Notebook, page 1

PreviewObjective


• Write a sentence concerning new information aboutthe moon.


• Plastic tack.• 1 globe.*t• 1 softball.• SCIENCE 4 Notebook Packet.*t• A three-ring binder.*


You will direct attention to a FindingOut box for the first time this year. Oneof your purposes in using these sec-tions of the student text will be to teachyour child to follow the directions forgathering materials, doing the activity,and considering the results of theactivity.

Introduce a Finding Out activity on page 13. Tellyour student to read silently the steps for doing theactivity. You or another child in the family will need toparticipate as a "friend" in the demonstration.Direct a demonstration. Instruct your student to readaloud the first step, which tells what materials shouldbe gathered. Allow him to get the materials and set themon a table.

14

DistanceAnother reason to believe that the moon is young is its

distance from the earth. Scientists have found that themoon is getting farther away from the earth each year.

They can measure how much farther away it is getting eachyear. Evolutionists could multiply the distance that themoon is moving away by one billion years (the age theythink the moon is). This would tell them that the moonshould be farther away than it is. Could the moon be as oldas the Evolution Model requires it to be?

______ ~23~8,~90~o~m~ite=5 0mean distance

The Purpose of the MoonHave Vall ever wondered why God made you? Or why

God mad~ anything? God made you and all things for Hisown glory (1 Chronicles 16:28, Romans II :36. and r Corin-thians 6:20; 10:31). But how can something like the moonbring glory to God? Read the following verses and seewhether you can find three ways that the moon can"declare the glory of God.""And God said. Let there be lights in thefirmament of theheaven 10 divide the day from the night; and let them be forsigns. and for seasons. and for days. and years: And letthem be fur lights ill the [irmament of the heaven to givelight upon the earth: and it W(l5 50." Genesis 1:14-15

Do you see that God made the moon and all "lights inthe firmament" to be for signs, for seasons. and for lights inthe heaven'!

If you do not have plastic tack, youmay substitute a small piece of mod-

~ eling clay.'--------- --

Your student should continue reading and followingthe steps. In Step 2, the globe should spin quickly,counterclockwise. The ball should move slowly aroundthe globe, counterclockwise. The same side of the ballshould be facing the globe at all times. In other words,by the time the ball has moved slowly around the earthone time, it should have spun around once. For everyrevolution around the earth, the moon rotates once.

In Step 3, when the globe has been turned halfwayaround, counterclockwise, the ball should be in the west,in relation to the United States.

Teaching the LessonDirect a text activity on pages 11-12 and 14-16. Usethe following questions to initiate your student's interestin what he is going to read.1. What three ways does the moon "declare the glory

of God"?2. How does the moon act as a light?3. What is the difference between the way ancient

people began a month and the way people todaybegin a month?

SCIENCE 4 HTE

11

Relative sizes of moons to the planets they orbit

v<,.~nus is to Titania,.."

planet

The Moon Is a LightAlthough the moon docs not make its own light, it does

reflect some of the sun's light. Look at thc chart, Since themoon is large for the size of the earth, it can reflect morelight to the earth than any other moons can to their planets,If the moon were just average in size, a moonlit nightwould be too dark for certain organisms,

The large dark areas on the side of the moon facing theearth do not reflect as much light as other areas, The farside of the 11100n docs not have as many dark areas, Whatwould happen if the moon moved so that we could see theother side? If that happened, we could see the morereflective side of the moon, and a moonlit night might betoo bright for plants and animals that need some timewithout much light,

12

Continue with discussion questions. After your stu-dent completes his silent reading, use the, followingquestions and statements as a guide to discuss.the pageshe read.

L What three ways does the moon "declare the gloryof God"? (to be signs.for seasons, andfor lightsin the heaven)

2, What kind of God could speak the universe intoexistence and then direct that universe to workconsistently for thousands of years? (a great God)Remind your student that the same God who didall that and who continues to uphold the world byHis power also protects and nourishes everyonewho comes to Him through His Son, Jesus Christ(Bible Promise: H, God as Father)

3, How does the moon act as a light? (It reflects someof the sun's light, just enough for the plants andanimals on earth.)

4. Have you ever seen the "face" or the "man inthe moon?" (Answers will vary.) The large darkareas that are always visible when the moon is fullor three-quarters visible (waning gibbous) make upthe face,

5, What is the purpose for the dark or dull areas onthe moon? (They are part of the reason the moonreflects the correct amount of light to the earth.)

Chapter 1: Lesson 4

About How the Moon Moves

L You will need plastic tack, a globe, and a softball,

2, Put a piece of plastic tack on the globe to show theplace where you live, Have a friend hold a softballabout a foot from tbe globe to represent the moon,Have him move the ball slowly around the globe as youturn it fast Turn both counterclockwise, This activitywill give you an idea of how the earth turns incomparison to the moon,

3, Now tell your friend to hold the moon steady while youslowly turn earth, Put the moon to the cast of the U.S,Turn the globe half way around, Where is the moon inrelation to the U.S, now? Is it in the west or the east?The rotation of the earth causes the moon to appear tomove across the sky,

6. What is the difference between the way ancientpeople began a month and the way people todaybegin a month? (In ancient times, each new moonsignaled the start of a month. Today, the year isdivided into twelve parts, each one a month andnone having any connection with the appearanceof a new moon.)

7. What is the purpose of the moon in the future? (Towarn people of the end of the age, the moon willturn blood red and will reflect little light, Its endwill come when there is a new heaven and a newearth.)

Conclude the discussion. In addition to the verses inthe student text, you may want to read some of thefollowing verses to your student: Joel 2:30-32; Matthew24:29-31; Acts 2: 19-20, Emphasize that as wonderful acreation as the moon is, it (as well as the sun and thestars) is inferior to its Creator. Furthermore, its futureend will fulfill God's purpose even as its present func-tions do,

13

15

The Moon Is a CalendarIn the ancient Near East the moon was an important

time measure. The people used each appearance of' the newmoon to start a "month." A merchant, for example, would

take out his account book to find out how much peopleowed him. The Latin word for account book is calends:from it we get the word calendar. But later, people found iteasier to divide the year into twelve parts. Each part hadabout the same number of days. So today the word"month" applies to the twelve sections of the year and hasno connection with the appearance of a new moon.

14

16 SCIENCE 4 HTE

The perfect design and function of the moon point 10 aCreator much greater than His Creation. Isaiah 40:25-26says, "To whom then will ye liken me. or shall I be equal?saith the Holy One. Lift up your eyes on high, and beholdwho hath created these things. that bringeth out their hostby number: he callcth them all by names by the greatness ofhis might. for that he is strong in power: not one faileih."

The End of the MoonGod promises that the muon will continue as long as the

earth remains. But when we have the new heaven and thenew earth. the moon's purpose will be over Revelation 21: 2:1tells about the light of the new Jerusalem: "And the cityhad no need of the SUllo neither of the moon. to shine in it:for the glory of God did lighten it. and the Lamb is thelight thereof."

16

Evaluating the Lesson

It is important for your child to havehis SCIENCE 4 Notebook Packet andthree-ring binder for this lesson.

Conduct a notebook activity on page 1. Instruct yourstudent to complete the notebook page, discussing atleast one new fact that he has learned about the moonin this lesson. When he has completed his writing, youmay want to provide an opportunity for him to read hisparagraph to the family. After you have read and com-mented on his paper, return it to your student to be keptin his science notebook.

Chapter 1: Lesson 4

name _

Complete these lentence' with Information Ihat you hive leamed In thll lessen about the moon.

We have been studying the history of the moon. Beforethis lesson I already knew that the moon

One new thing that I learned in this lesson is

The most interesting part of this lesson was

'1990 Bob Jones UniVBOIlty Preas. Reproclucllon prQhlbUed.

D Sdence4Notebook P.cket

lesson 4

ev~lualjng 1M LI!UOtl

For Your InformationAmong Christians there are different views of cre-

ation. Some Christians believe that the days in Genesis1 are twenty-four-hour periods (the short-day theory).Other Christians interpret the seven days of creation asseven ages (the long-day or day-age theory). Some whohold this theory do so only to allow for theistic evolu-tion. Some Christians hold yet another theory (the gaptheory), placing a long period of time between Genesis1: 1 and 1:2. Gap theorists believe there was a "firstcreation," which was probably destroyed by Satan'sfall, alluded to in Isaiah 14: 12-17. This theory allowsfor an "old earth" without abandoning the creationaccount in Genesis. For further discussion of these the-ories and their implications, see pages 174-76 of BIOL-

OGY for Christian Schools® (2nd ed.), published by BobJones University Press.

17

CHAPTER

2Insects, Arachnids,and Myriapods

~

Lessons 5-10

I ~ Insects,Arachnids, andMyriapods

17


In these lessons your student will use matching gamesand demonstrations as he learns how to identify and clas-sify insects. The chapter concludes with your student usinga simple classification key to prepare his own collectionfor display.

Materials ------The following items must be obtained or prepared be-


* Several field guides or resource books about insects(Lesson 5)

* 1 four-holed bubble pipe (Lesson 6)* Ants for the ant farm (Family Time 8)* Ants (different type from the ants in the ant farm) for

experiment on Day 4 (Lesson 8)* Tiny pieces of banana and apple (Lesson 8)* Bits of walnuts (Lesson 8)* Small magnifying glasst (optional) (Lesson 9)* 5 insect pins (optional) (Lesson 9)* Spider's web (Lesson 10)

19

Lesson 5Insect Orders

Text, pages 18-20

PreviewObjectives


• List the common characteristics of insects.• Describe the stages of complete and incomplete

metamorphosis.• Identify the characteristics and examples of the Order

Orthoptera.


• Home Teacher Packet, pp. 5-6.• 1 plastic comb.• 1 metal nail file.• A Write It flip chart.• Several field guides or resource books about insects. *

Prepare:• The review game board by tracing the grid from the

game pieces on page 6 of the Home Teacher Packetonto a blank page of the Write It flip chart. Label thesquares i-9. (NOTE: See Figure 5-1.) Cut the gamepieces apart.

1 2 3

4 5 6

7 8 9

Figure 5-1

Notes ------You will want to catch several crickets for your student

to observe as you study this lesson. Crickets stay in shel-tered places during the day and come out at night to huntfor food. You can try looking for them under rocks andboards or in tall grass and bushes.

20

You may want to call a cooperative extension agent inyour area to set up an appointment to see his insect col-lection during these lessons on insects. Your student willbe able to see a variety of insects. The extension agent canalso answer many of your student's questions.

The following books are good resources for this chap-ter. Check your local library to see if it carries these titlesor if the librarian can recommend some others.

• A Field Guide to the Insects of America North ofMexico by Donald J. Borror and Richard E. White(from The Peterson Field Guide Series).

• Field Book of insects by Frank E. Lutz (from Put-nam's Nature Field Books).


Direct a demonstration to show the difference be-tween the musical abilities of grasshoppers andcrickets. List the following phrases on the Write It flipchart: uses its voice, uses its legs, uses its wings. Thenask your student which method he thinks the cricketuses to produce its song. (NOTE: Your student may besurprised to find out that crickets rub their wings to-gether, not their legs, to produce sound.) Tell him thatgrasshoppers rub the insides of their back legs againsttheir wings to produce sound. But crickets sing by rais-ing their wings and moving them briskly across eachother like opening and closing scissors. Tell your stu-dent that male crickets are usually the only ones thatcan sing.

Give your student a comb and a file. Explain thatthe ridges on the grasshopper's legs are similar to theteeth on the comb. The file is similar to the ridged veinson the cricket's wings. Ask him to rub his thumbnailagainst the comb and then against the file.

You may wish to relate the followinginteresting information to your child.In the Orient crickets are sometimesused as an insect alarm system. Ahomeowner sets up his "insect alarm"by placing about the house small cagesfilled with crickets. Night after nightthe crickets fill the air with their song.The owner soon becomes accustomedto the sound and is hardly aware of thechirping crickets. When an intruderenters the home, the crickets immedi-ately stop chirping, and the sudden si-lence wakes the owner from his sleep.

SCIENCE 4 HTE

The InsectsDid you know there are over 800,000 different kinds of

insects? And some scientists think there arc at least ROO,OOOmore that have not yet been studied!

Yet despite their great numbers, they all have severalcharacteristics in common. They all have exoskeletonsmade of chitin. They all have jointed appendages. or legs,that are paired equally. These characteristics make themarthropods. But they also have characteristics that make

What can you see about the number of legs theseanimals have'? They all have three pairs of legs. What doyou observe about how their bodies look? They have threebody segments, ordivisions: the head. the thurax, and theabdomen. Can you make a generalization about theirheads? Most have one pair of antennae on their heads.

What three characteristics can }OU say insects have'!Insects also have characteristics that make them distinctfrom one another. Scientists use such characteristics todiv ide insects into smaller group'. Why do you think thatscientist; make these divisions?

18

Teaching the LessonDirect a text activity on pages 18-20. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. What characteristics do adult insects have?2. What is metamorphosis?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. What characteristics do adult insects have? (exo-

skeletons, jointed appendages, three body parts,six legs, and usually one pair of antennae)

For the next four questions, display thespider and other non-insects on page 5of the Home Teacher Packet.

2. How many legs does the spider have? (8)3. How many body parts does the tick have? (2)4. Do the daddy longlegs and the roly-poly have an-

tennae? (no)5. Do these animals fit the description of insects? (no)

Explain to your student that although these animalsare arthropods, they are not insects.

Chapter 2: Lesson 5

The Grasshopper GroupThe grasshopper, the praying mantis, the cricket, and

the walking stick are members of the same group, or order.These insects have jaws that chew from side to side. Theymostly chew up plants.

The praying mantis, however, eats other insects -evenother praying mantises. Can you see in this picture how thepraying mantis got its name?

All insects in this group have two pairs of wings, onepair like heavy paper and the other pair like crisp, clearsilk. Both pairs fold up, the thin pair closing under the

6. How would you group the insects for people tostudy? (Some answers your student may give arecolor, number of wings, and size.) How manygroups of words is the English language dividedinto in a dictionary? (26 groups based on the al-phabet) Similarly, the 800,000 different kinds ofinsects are divided into 26 groups or orders byscientists (entomologists) who study insects. Theystudy the wings, mouth parts, and legs to helpseparate the insects into groups.

7. Tell your student that the insect order he is study-ing today is the Order Orthoptera. Explain thatortho- means "straight" and -ptera means"wing." Ask him to look at page 19 and list someinsects that belong in this order. (grasshopper,praying mantis, cricket, and walking stick)

8. What is metamorphosis? (the special changes in-sects undergo during growth) Nearly all insectsundergo one of two types of metamorpho-ses-complete or incomplete.

9. What are the stages of incomplete metamorphosis?(egg, nymph, adult)

10. What stage does the top picture on page 20 show?(nymph) What do you think this nymph will growup to be? (a grasshopper)

11, How is a nymph different from an adult? (Thenymph looks like a smaller adult without wings.)

19

21

Young grasshoppers must go through a change to looklike their parents, This change is called metamorphosis,Metamorphosis comes from the words meta and morphi,which means "form," What do you think meta means?

Many invertebrates also go through metamorphosis.Some, like the grasshopper, go through incompletemetamorphosis.

The grasshopper starts out as an egg. It then becomes anymph The nymph looks like the adult but is smaller andhas no wings, Then it finally becomes an adult grasshopper.How many steps are there in incomplete metamorphosis?

20

Conclude the discussion. Ask your student whether heremembers the stages of complete metamorphosis fromearlier science lessons in grade 2, Remind him that abutterfly is an insect that goes through complete meta-morphosis. Ask him to list the stages. (egg, larva, pupa,and adult) Does a nymph in incomplete metamorphosislook like the adult insect? (Yes, it is smaller and has nowings.) Do the larva and pupa in complete metamor-phosis look like the adult? (No, each stage has its ownappearance and behavior, For example, the active, hun-gry larva changes into the resting.fasting pupa.)


You may want to color the game piec-es before beginning the review game,or you may allow your child to gluethe pieces to the game board and colorthem after he has completed the game,

Direct a review game. Use the prepared game boardon the Write It flip chart. Tell your student that you willbe asking questions to review pages 18-20, Allow himto reread these pages quickly in preparation for thegame. Point to the grid on the flip chart. Explain that

22

each square designates a piece of a puzzle. The puzzleis a picture of an insect in the Order Orthoptera. Whenhe answers a question correctly, he may choose onepuzzle piece to add to his grid. Challenge him to com-plete the puzzle in as few questions as possible. Hereare some questions you might ask for the review game:

I, How many body parts does an insect have? (3)2. How many legs does an insect have? (6)3. How many antennae does an insect have? (2)4. What type of skeleton does an insect have? (exoskeleton)5, What is the exoskeleton made of? (chitin)6. How many wings do grasshoppers have? (4 wings or 2

pair)7. Describe the grasshopper's upper pair of wings. (like

heavy paper)8. Describe the grasshopper's lower pair of wings, (crisp,

clear, silky)9. How many stages are in incomplete metamorphosis? (3)10, Name the three stages. (egg, nymph, adult)II, How many stages are in complete metamorphosis? (4)12. Name the first two stages, (egg and larva)13, Name the last two stages, (pupa and adult)14. Name an insect that goes through incomplete metamor-

phosis. (grasshopper, cricket, dragonfly, bug, etc.)15. Name an insect that goes through complete metamor-

phosis. (butterfly, moth, beetle, fly, bee, ant, etc.)

For Your InformationYou should be aware that the characteristics (such

as six legs) listed for insects are for adult insects, Manyinsect larvae have 6 legs as well, but there are othersthat do not Caterpillars seem to have more than 6 legs,although the first 6 are the only ones considered to betrue legs, The others are prolegs, Fly larvae have nolegs at all.

The following list gives the names of the nine com-mon insect groups discussed in this chapter as well asthe corresponding order names and their meanings. Theorder names describe a distinct characteristic of the in-sects in that group.Grasshopper group-Order Orthoptera-straight wingDragonfly group-Order Odonata-toothed (NOTE: This

group is the only one in the list that does not describethe insects' wings, Toothed refers to the strong-toothed jaws of the dragonflies.

Aphid group-Order Homoptera-same wingBug group-Order Hemiptera-half wingMoth and butterfly group-Order Lepidoptera-scale

wingBeetle group-Order Coleoptera-sheath wingFly and mosquito group-Order Diptera-two wingsBee and ant group-Order Hymenoptera-membranous

wingFlea group-Order Siphonaptera-siphon (sucking mouth

parts) without wings

SCIENCE 4 HTE

The order names are given for yourinformation and for your child if he istruly interested in insects. The com-mon insect names are all your childshould be expected to know.

The praying mantis is the gardener's friend. Its vo-racious appetite for all kinds of insects (including otherpraying mantises) helps rid gardens of many insectpests. The praying mantis seems afraid of nothing andwill attack insects many times larger than itself. Onecharacteristic unique to the mantis is its ability to turnits head like a human. Unlike the cricket, grasshopper,and katydid in this insect order, the praying mantismakes no sound.


Lesson 6Dragonflies,Aphids, andTrue Bugs

Text, pages 21-23

PreviewObjectives


• Mimic the feeding actions of a nymph dragonfly.• Solve a word problem about the dragonfly's life

cycle.


• 2 feet of yam.• Small piece of scrap paper.• I stapler.• I four-holed bubble pipe. *• Bubble solution.

Prepare:• The strand of yam by stapling the small piece of scrap

paper to the end.

NotesBubble solution can be made by mixing 1 part liquid

dishwashing detergent (Dawn works very well) to 9 partswater.


Direct an activity of the nymph feeding habits of thedragonfly. Tell your student that one of the insectgroups he will be studying today is the dragonfly group.Read the following paragraph describing how thenymph dragonfly hunts its food.

Unlike the adult dragonfly, which catches its foodwhile darting back and forth in the air, the nymph

24

hides and waits for its food to swim within reach.While it waits, its long unusual lower lip is pulledback and folded underneath its head, covering part ofits face like a mask. When food is within reach, thelip quickly unfolds, snatching up its prey. Two hooksat the end of the lip firmly hold the prey as the lipsnaps back in place. Now the food is within reach ofthe nymph's sharp jaws. While the nymph cuts upand chews its food, the lip acts as a sort of plate tocatch any "crumbs" that may fall from its jaws.

Lead your student in an imitation of the nymph feedinghabits of the dragonfly. Instruct him to stand up andfollow your motions. First bring your right elbow closeto your chest. Next, place your right hand over yournose and mouth, resting your chin in the curve of yourpalm. Then quickly reach out your right hand pretendingto grasp something and then fold your arm again andreturn your hand to your chin. Ask your student tocontinue mimicking the feeding actions of the nymphdragonfly. Begin walking toward your student, danglingthe strand of yam in the air. Tell him that this is amosquito larva and that he is a hungry nymph. Allowthe hungry "dragonfly nymph" to try to catch the food.

SCIENCE 4 HTE

The Aphid GroupThe insect. in this group can look like tiny tents when

they are sitting still. They fold their wings >(1 that the,touch at the upper edges and spread out over their bodies.Most insects in this group have two pairs of wings. butsome have none at all, How do you think scientists tell aninsect is an aphid if it has no wings'!

All aphids suck the juices out of plants. Most of themdo a great deal of damage to gardens and house plant>. Onemember or the aphid group is useful. though. The lac insectgives a sticky liquid that is used to make shellac. a thinvarnish for wood.

Another member, the cicada. or seventeen-year locust.lays its eggs in trees. When the young hatch. they crawl tothe ground and burrow into the soil. The nymphs live thereon the juices from the plant roots. After seventeen years.they climb back up the tree and become adult cicadas.

22

Direct a demonstration. Tell your student to turn topage 22 and to name the next insect group he will bediscussing. (the aphid group) Explain that there are alsosome interesting insect nymphs in the aphid group. Oneis called the spittlebug. Ask your student to try to guessthe unique characteristic of this insect based on its name.Fill a bubble pipe with solution and begin blowing amass of bubbles. Ask your student to extend his indexfinger into the air. Place a cluster of lather on his finger.Explain to the him that this is very similar to the bubblehouse the spittlebug builds for itself. The nymph re-mains under the protection of the bubbles unless it isdisturbed. Tell your student that only the nymphs makethese bubbles. Scientists believe that the bubbles pre-vent the insects from drying out and also protect themfrom their enemies.

Chapter 2: Lesson 6

The Dragonfly GroupThe dragonfly and the damselfly arc members of this

group. They both have thin bodies shaped like darningneedles. Dragonflies can be up to three Inches long:damselflies are somewhat smaller.

They both have two pairs of wings. like veinedcellophane. I he wings of dragonflies usually Slick ...traightout from their bodies. 1he wings of damselflies arc heldtogether above the bod).

These insects eat mosquitoes. gnats. praying mantises.and just about any other insect. The) lay their eggs in waterand on plants such as the water iiI) and the cattail. Wherewould be a good place to go if you wanted to see adragonfly'

21

Teaching the LessonDirect a text activity on pages 21·23. Use the follow-ing questions to initiate your student's interest in whathe is going to read.

1. What insects does the adult dragonfly eat?2. What insects look like a tiny tent when they are

sitting still?3. What is a bug?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.I. What are the stages of incomplete metamorphosis?

(egg, nymph, and adult) All the insect groups intoday's lesson undergo incomplete metamor-phosis.

2. What do you think happens to the outer coveringof the nymph as it grows? (Answers will vary.)Explain that the dragonfly does a tremendousamount of growing and changing while in itsnymph stage. Unlike human skin, the outer coy-

25

The Bug GroupWhat is a bug? Many people call any insect or even a

spider or a centipede a bug. Some people with the !1u saythey have "come down with a bug." Police detectives find alistening device on a telephone and report, "This phone hasa bug." if a machine docs not work right, the mechanicmight explain: "I don't have all the bugs out yet."

But when scientists say bugs. they mean a special groupof insects that have long. piercing mouth parts, almost likethin, miniature beaks. Most bugs have flat. oval bodies andtwo pairs of wings. Both pairs of wings are thin. but thefront wings are thicker where they join the body andgradually get thinner. A few bugs do not have wings. Howdo we know they are bugs?

Some common bugs are stinkbugs, bedbugs, and waterstriders. Water striders can walk on the surface of pondsand streams.

The giant water bug lives in lakes and ponds. Some getup to four inches long and eats snails, minnows, and evensmall snakes. it has strong forelegs and a nasty bile.

Where do you think bedbugs live? How do you thinkstinkbugs got their name? How do you think the expression"Don't bug me" came about'!

23

ering of insects does not grow constantly. As thenymph becomes larger, its outer covering becomestighter until finally the covering splits open and anewly covered nymph emerges, This process iscalled molting. The nymph will undergo severalmolts before it is fully grown.

3. What insects does the adult dragonfly eat? (mos-quitoes, gnats, praying mantises) The dragonflylives up to its name because it is a ferocious hunter.

4. Would the nymph eat the same type of food as theadult? (no) Why not? (The nymph lives in thewater.)

5, What type of food do you think the aquatic nymphdragonfly would eat? (The nymph eats many im-mature insects such as mosquito larvae. Then asthe nymph grows larger, it adds larger prey suchas tadpoles, shellfish, and young fish to its diet.)

6. What insects look like a tiny tent when they aresitting still? (insects in the aphid group)

7. How do insects in the aphid group get their food?(They suck the juices out of plants.) Tell your stu-dent that these insects have "built-in" drills-sharpmouth parts to pierce the stems of plants and reachthe juice.

8, What is a bug? (When scientists refer to bugs, theymean a special group of insects that have long,piercing mouth parts and two pair of wings.)

26

Conclude the discussion. Tell your student that bubblesplay a role with some insects in the true bug group.Water boatmen, backswimmers, and the giant waterbugs are all insect "scuba divers" that trap air bubblesclose to their bodies. If your student has seen a humanscuba diver in action, ask him to list some of the equip-ment the diver uses. (mask, air tanks, fins, weight belt,etc.) Tell him that people need all this extra equipmentto function well underwater. Insects like the giant waterbugs and water boatmen, however, do not require extraequipment. God has designed the bodies of these insectsto function well underwater. (Bible Promise: 1. God asMaster) Ask your student why the insects would needto take air with them down into the water while theyswim and feed. (The insects use the trapped air tobreathe.) Tell him that when an insect needs a newsupply of air, it rises to the surface and traps more air,

Evaluating the LessonSolve a word problem. Tell your student to take out apiece of paper and write down the months of the yearon the first twelve lines. Explain that you will be givinghim some information to solve a word problem aboutthe green darner dragonfly's life cycle. Read the follow-ing paragraph to your student.

The green darner belongs to the family of drag-onflies with the largest and most powerful wings.Easy to spot with its metallic green body, the greendarner can be found nearly anywhere in the UnitedStates as well as in parts of Canada. The eggs of thegreen darner take about two weeks to hatch. Whenthe nymphs hatch, they live underwater for nearlytwelve months. During this time the nymphs growand develop. Finally the nymphs crawl out of thewater and shed their skin. These newly winged adultslive about one month.Instruct your student to write the word eggs next to

the month of ApriL Then ask him in what month wouldhe most likely be able to see the adults flying around ifthe eggs of a green darner were newly laid in mid-April.Review that eggs take two weeks to hatch, nymphs taketwelve months to grow and develop, and adults live forone month. The answer to the problem is May.

Make a comparison between the green darner's lifecycle and the life cycle of humans by asking the follow-ing question, If people had a similar life cycle to thegreen darner, in which of the three stages-child, teen-ager, or adult-would they spend the longest part of theirlives? (teen-ager) Tell your student that if he lived tobe 81 years old, 72 of those years would be as a teen-ager.

SCIENCE 4 HTE

For Your InformationBedbugs are wingless, bloodsucking bugs that feed

on the blood of animals and people. The bugs are small(i" long) and hide during the day under mattress but-tons, in cracks in beds or floors, or under wallpaper.During the night they come out and suck the blood ofhumans. The bite of a bedbug usually produces onlyslight irritation, but it m~y cause a large welt. Bedbugsare found all over the world and can be easily pickedup in hotels, subways, arid infested homes. Although ahouse is kept clean, bedbugs can still be living there.

The aphids that live during the summer can repro-duce without mating. These aphids do not lay eggs butbear their young alive. Every aphid in the crowd is afemale, and every baby that is born is also a female. Injust a few days after birth an aphid begins producingyoung of its own. If everyone of its offspring remainedalive, one aphid could produce 1,560,000,000,000,000,-000,000,000 (one septillion, five hundred sixty sextil-lion) offspring in one year.


FamilyTime 7

Finding OutAbout Insects

Text, page 34


• I plastic margarine container.• 5 resealable sandwich bags.• 2 Popsicle sticks or flat toothpicks.• 2 small weighted objects (large spool of thread or asmall box of matches).

NotesIn Chapter 2 your child has been studying insects.

By the time he has completed this chapter, he will havestudied the following groups of insects: grasshoppers,dragonflies, aphids, bugs, moths and butterflies, beetles,flies and mosquitoes, bees and ants, and fleas. To pro-vide him with first-hand experience in observing andidentifying insects, he needs to collect five differentkinds of insects (for example, five ants would not beacceptable) and have them ready for Lesson 9.

InstructionsDirect your child's attention to the Finding Out ac-tivity on page 34. Ask him to read aloud Steps 1-3 tothe family. Tell him the whole family will help him findinsects, but it will be his responsibility to make surethat the animals are true insects. Ask him what char-acteristics he will be looking for in each insect. If he ishaving difficulty listing the characteristics of insects,ask him to read page 18 in his textbook. (Six legs, threebody parts, and usually antennae should be evident.)You will want to estimate the date of Lesson 9 so thatyour child will know how much time he has to work onthis project. You should also encourage your child totry to choose larger insects. The bigger insects are easierto handle when going through the classification key.

This insect project does not necessarilyneed to be done in one evening. Theinsects may be collected over a periodof days as long as they are ready forthe presentation of Lesson 9.

28

About InsectsI. Get a plastic margarine container with a lid and fivesealable sandwich bags.

2. Catch an insect in the container and then put it into asandwich bag. Without crushing the insect, try to keepits wings spread. Catch and seal at least five insects thisway. Try to get insects that look as different [rom eachother as possible.

3. Put the bags into the freezer for an hour.

4. Bring your insects to class in the bags. With yourteachers help, classify and mount your insects.

5. Display your mounted insects with those of yourclassmates.

34

Spreading the wings of butterflies and dragonflies.The following information explains how to spread thewings of butterflies and dragonflies.1. Remove the insect from the freezer and carefully

take it out of the bag.2. Place the insect on a flat surface and ask a parent

or friend to gently hold the insect's body. Take twoflat toothpicks (or two Popsicle sticks) and slipthem between the insect's wings. Slowly spreadthe wings apart so that they rest on either side ofthe body.

3. Ask your helper to place a small weighted object(large spool of thread or a small box of matches)on top of each toothpick or stick holding down thewings. (NOTE: See Figure 7-1.) Allow the insectto remain in this position for one or two days.Return the insect to the bag.

Figure 7-1

SCIENCE 4 HTE

Lesson 7Butterflies,Beetles, and

FliesText, pages 24-27

Notebook, pages 2-3

PreviewObjectives


• Differentiate between moths and butterflies.• List the characteristics used in identifying moths andbutterflies.


• 1 flashlight.


You will want to catch fireflies (light-ning bugs) for your child to observethe flashing pattern as you introducethis lesson.

Discuss fireflies. Show your student the fireflies youhave caught. Ask him what he thinks is the purpose ofthe lightning bugs' flashes. (Some responses may be tolight their way or to find each other.) Tell him that themale fireflies use their flashes to find a mate. Becausethere are several different kinds of fireflies, the malesin one group (species) can tell the females belonging tothe same group (species) by their flashing responses.The pattern differs for different groups (species) offireflies.

Chapter 2: Lesson 7

Direct a mock firefly demonstration. Turn off thelights in the room and tell your student that the firstpattern that you will flash with a flashlight is that of themale firefly. Flash the pattern-flash, flash, pause, pause,flash, flash. Next tell him that you will flash two femalepatterns-(l) pause, flash, pause, flash and (2) pause,pause, pause, flash, flash, flash. Tell your student thatthe male firefly is looking for the female with the patternpause, pause, pause, flash, flash, flash. Flash both fe-male patterns again and allow your student to try to findthe correct one. Try to observe the flashing pattern ofthe fireflies you have caught.

Tell your student that today he will be studyinginsects belonging to three groups: butterflies, beetles,and flies. The last lesson discussed insects belonging tothe bug, aphid, and dragonfly groups. Ask him to tell inwhich of these six insect groups he thinks lightning bugsor fireflies belong and to give his reason(s) for choosingthat group. (bugs-lightning bugs, flies-fireflies) Tellyour student that in spite of their names, lightning bugsare beetles. Beetles make up the largest group of all theinsects.

29

The Moth and Butterfly GroupAt first glance, moths and butterflies look much alike.

But take a close look at the butterfly and moth pictured

here. Can you find two ways moths are different frombutterflies? How is a butterfly's body different from amoth's? How are the moth's antennae different from abutterfly'S?

Moths and butterflies have large, delicate, and oftencolorful wings that are covered with tiny scales. Mostmoths do not have all the beautiful colors on their wingsthat butterflies do.

Most moths and all butterflies have long tube-likemouths that can reach deep into flowers for nectar. a sweetliquid. When not in use, the tube is coiled up under thehead.

Monarch butterflies live in the northern United Statesduring the summer. In early fall they gather in large groupsand fly to the Gulf and Pacific coasts. When they land, theylook like great orange clouds billowing down on the trees.In the spring, they fly north again.

24

Teaching the LessonDirect a text activity on pages 24-27. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. What kind of metamorphosis do butterflies and

moths go through?2. How many pair of wings do beetles have?3. What does a mosquito like to eat?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Use the first two points on the chart on page 25 to

compare the pictures of a moth and a butterfly onpage 24. Which insect is a butterfly and which oneis a moth? (The one on the right is a butterfly, andthe one on the left is a moth.) Tell your studentthat the butterfly in this picture is not resting withits wings straight up (point 3 in the chart) becauseits wings have been spread for mounting. The but-terfly has been preserved in an insect collection.

2. What kind of metamorphosis do butterflies andmoths undergo? (complete metamorphosis)

3. Look at the chrysalis of the monarch butterfly onpage 25. What stage of the butterfly'S life cycle ispictured there? (pupa)

30

Monarchs go through complete metomorptiosis.Complete metamorphosis begins with an egg. The larvahatches [rom the egg. -1he larva then goes into the pupastage, or resting period. The pllP~ builds a chrysalis andbecomes encased in it. After a while. an adult monarchemerges from the chrysalis,

Some butterflies and many moths are harmful. Thelarvae, or caterpillars! eat fruits, vegetables, tree leaves. andeven cotton or wool. The gypsy moth, for example, candestroy whole forests. stripping the leaves from trees.However, most of these insects do help pollinate flowers.and the silkworm moth gives liS what we need to make silkcloth.

Butterflies1. Thin bodies2. Slender antennae3. Rest with wings straight up4. Fly mostly during the day5. Develop from a chrysalis

Moths1. Fat bodies2. Feathery antennae3. Rest with wings straight out4. Fly mostly at night5. Develop from a cocoon

4. Look at the fifth point in the chart on page 25. Isthe pupa stage of the moth the same as that of abutterfly? (No, the moth spins a soft cottony cocoonrather than a hardened chrysalis case.)

5. Unlike the fireflies that depend on sight, the mothsand butterflies depend on their sense of smell tofind their mates. These insects do not have a noselike a human being. What part of their bodies doyou think they smell with? (Your student's answermay vary. Moths and butterflies smell with theirantennae.)

6. Look at the fourth point in the chart on page 25.Can you think of an experiment that you could doat home that would show that butterflies are moreactive during the day or that moths are more activeduring the night? (Encourage your student to thinkof workable, practical ways to show this difference.A suggestion might be to count the number ofmoths vs. butterflies flying around an outside lightat night or around a group of flowers during theday.)

7. How many pair of wings do beetles have? (two)Describe the front wings. (hard, shiny, and shell-like) How is the second pair of wings protected?(underneath the front pair)

8. Look at the picture of the mosquito on page 27.This mosquito is not the same kind of mosquito

SCIENCE 4 HTE

25

The Fly and Mosquito GroupWho hasn't had a housefly pester him at a meal, and

who hasn't felt a mosquito helping itself to a little blood"The insects in this group arc some of the least useful andmost disliked insects around.

All members of this group have one pair of wings: thin,almost transparent, and veined. Most have sucking mouthpans. Deer flies and tsetse flies, for example and,certainly, mosquitoes do. Houseflies have spongingmouth parts.

Because flies lay their eggs in manure and walk in dirtyplaces, they pick up bacteria on their claws and mouthparts and on the sticky hairs of their legs.

The claws, pads. and sticky hairs help them walk almostanywhere even on glass. When the Ill' lands on somconc'sfood, it can spread disease by rubbing some bacteria fromits feet or mouth parts onto the food.

The mosquito likes to feed on animal and human blood.It spreads disease when it bites a sick animal or human andthen flies off to bite another, leaving some diseased bloodin its next victim.

Mosquitoes carry malaria from person to person. Thisdisease was once thought to be brought on by bad air. Canyou see how malaria got its name: mal- (bad) + aria (air),'

27

that spreads malaria. Do you think the mosquitopictured is a male or female mosquito? (a female)Your student can observe that the female mosquitoin the picture has antennae with a few short hairsarranged along its length, The hairs on the malemosquito'S antennae, however, are so long andthick that the antennae look more like delicate,fancy feathers. These antennae are especially im-portant for the male mosquito to find his mate.

9. How does the moth use his antennae to find a mate?(He uses the antennae to smell her.) How do youthink the mosquito uses his antennae to find hismate? (Answers will vary. He uses his antennae tohear her. When the female mosquito flies, the humof her wings draws the male to her.)

Conclude the discussion. Tell your student that malemosquitoes have shorter mouth parts than the femalemosquito pictured in the textbook. One reason for thisis the different foods that male and female mosquitoeseat. Female mosquitoes feed on the blood of animalsand people as well as the juices of plants. The males,however, feed only on the juices of plants. The bloodmeal is usually necessary for the female to produceeggs,

Chapter 2: Lesson 7

The Beetle GroupThere arc at least 300,000 kinds of beetles. Some of

them arc known by the name beetle, but many of them arenot. The Japanese beetle, the boll weevil, and the ladybug(ladybird beetle) belong to this group.

Beetles have two pairs of wings. The front wings arehard and usually shiny. When folded back, these wingsmake a shell-like covering with a straight line down theback.

Many of these insects eat plants, such as potato plants,wheat, and colton, that are useful to people. A fewhowever, like the ladybug, eat other insects.

If you find a ladybug, what should you do"

26

31

name _

Ullng 1M ten distinguishing charKlert,tlc, lI.ted below, Identity each Insect .1 • bunerfly or a moth.L~t the numbtrl Or tf'MehlrKt.rttttet you used Inthe .pace below e.ch Insect diagram.

Butterfli •• Moths

I. Thin bodies 6. Fat bodies7. Feathery antennae8. Rest with wings straight out9. Fly mostly at night10. Develop from a cocoon

2. Slender antennae3. Rest with wings straight up4. Fly mostly during the day5. Develop from a chrysalis

1,2,34

·'i11OBobJontlUnlv,r.ltyPr.II,ReprodlicUonprohlblled.

D Sdence4NoIebook' ••••••

lel50n7

Evaluating tn.l.uon

Evaluating the LessonDirect a notebook activity on pages 2-3. Direct yourstudent's attention to the insect drawings on the note-book pages. Tell him that he must identify each insectas either a moth or a butterfly by using the characteris-tics given in the chart on page 2. When he has properlyidentified an insect, he should write the correct label onthe first line below each insect. Then he should fill inthe second line below each drawing with the specificcharacteristics he used from the chart. Tell him thatsome insect drawings may show only one distinguish-able characteristic; others may show several.

For Your InformationMany of the common butterflies in the United States

belong to the family ofbrush-footed butterflies. If some-one were to count the legs of this butterfly, it wouldappear that they had only four legs and not the six thatare standard for all insects. In reality there are six legs,but the first two are so short and hairy that they look

32

5

106,7,8

like little brushes close to the butterfly'S head.One of the most devastating diseases of tropical

regions is malaria. Malaria is passed on to humans bythe female Anopheles mosquito. The malarial parasitesenter the bloodstream via the mosquito's saliva. Onceinside a human, the parasites penetrate the cells of theliver, and they grow and reproduce in the liver cells forabout two weeks. Eventually they invade the blood-stream. When the parasites enter red blood cells, theyagain begin to reproduce. Eventually the blood cellsburst, releasing new parasites that may invade otherblood cells. This periodic rupturing of red blood cellscauses the violent fits of chills and fever that character-ize malaria.

Luciferase and luciferin are the substances that helpmake the rear part of a firefly's tail glow. When thesesubstances combine with oxygen and other ingredients,they convert chemical energy to light, causing the fireflyto glow. Unlike the light that man produces throughchemical reactions, the light of the firefly produces noheat. God's design is evident even among these smallcreatures.

SCIENCE 4 HTE

FamilyTime 8

Finding OutAbout Ants

Text, page 30


• 1 large wide-mouthed jar.• 1 sealed can or cardboard tube (about 1" smaller in

diameter than the jar).• Slightly damp soil and sand.• Small sponge.• Swatch of loosely woven cloth.• Black construction paper.• Cellophane tape.• 1 large rubber band.• Ants for the ant farm. *t

NotesTraditional ant farms complete with mail-order ants

may be purchased from large toy stores and pet shops.Ants and ant farms can also be purchased from a scientificsupply company, such as Nasco or Carolina BiologicalSupply Company. (NOTE: See addresses below.) Your antsupply can also be collected from a nearby yard as sug-gested in this Finding Out activity.

• Nasco901 Janesville AvenueFort Atkinson, WI 53538

• Carolina Biological Supply CompanyBurlington, NC 27215

Two to three days before Lesson 8 isscheduled you will need to collect theant specimens and assemble the ant jar.You will want to instruct your child inthe handling of ants so that he will notbe bitten.

Chapter 2: Family Time 8

About AntsI. Get a large, wide-mouthed jar: an unopened can (large

enough to leave one and one-half inches between it andthe sides of the jar); some soil; bread crumbs. jelly. orsugar; a small sponge; a swatch of loosely woven cloth;black construction paper; a large rubber band: andsome ants.

2. Put the sealed can inside the jar and fill the space leftwith soil to within one inch of the top. Place the foodand the sponge dampened with water on top of the soil.Put in the ants. Cover thejar with the loosely wovencloth and secure with rubber band.

3. When no! observing the ants, cover the outside of thejar with black construction paper. Try giving the antsdifferent kinds of foods. Record your observations overa period of a week.

30

Instructions1. Direct your child's attention to the Finding Outactivity on page 30. Ask him to read this page silentlybefore beginning this activity.

2. Obtain the specimens. To gather ants out in the field,make sure that your child collects all his specimens fromone specific area. Choose a type of ant (for example,little black garden ants) that makes its nest just belowthe surface of the ground. A good place for finding antsis under large rocks. As your child gathers the ants, takecareful note of any food that may be in the area. Someants eat seeds, fungi, and other plant matter. This infor-mation may be important if he chooses to keep the antfarm after the experiment is over. (NOTE: A perfect dietfor the ants can be made by mixing one part sugar water,one part egg white, and one part melted butter. A pieceof some other soft insect may be given to the ants oncea week.) As your child collects the ants, take specimensfrom inside the nest as well as outside the nest. Thoseoutside the nest may be food gatherers or soldiers. Thoseinside the nest may be responsible for tending the youngor larvae. He may notice white specks in the worker'sjaws. These are eggs or larvae being moved by ants.

33

Also, look for pupae, which look like small kernels ofpuffed rice, and collect some of them. Continue diggingcarefully through the nest while looking for a queen. Aqueen is much larger than the workers, and her thorax(second body division) is humped where she used tohave wings. Chances are likely that you will not capturea queen ant, but your child should be able to observethe activities of the other ants. The colony will not lastas long without a queen.3. Assemble the jar for the ants. Place the sealed can(or cardboard tube) inside the jar. (NOTE: This arrange-ment will force the ants to build their tunnels near thesides of the jar where your child can observe them.)Sprinkle a mixture of slightly damp sand and soil aroundthe can or tube until the jar is filled to an inch from thetop. Place the ants in the jar and add some food. Set adamp sponge on top of the soil. This drinking spongeshould be kept damp at all times. Cover the jar with theloosely woven cloth, and secure the cloth with a rubberband. Construct a tube of black construction paper to fitaround the glass jar. Keep the jar covered when no oneis observing the ants at work and make sure that it isplaced away from heaters and cold windows. Frequentchanges from dark to light as well as frequent changesof temperature are harmful to the ants. Now that the antcolony is set up, allow a day or two before your childbegins his observations.

34 SCIENCE 4 HTE

Lesson 8

ObjectivesGiven proper instruction, your student will be able to

do the following:• Compare the body structure of bees and ants.• Compare the social activities of bees and ants.

were the first food-finding ant to find food for the colonyand that you left an odor trail of scented paper on thefloor from the food back to the starting place. He, asanother ant, will crawl along the floor, following thescented trail to find the food. Blindfold your student andallow him to smell the scent before beginning. Whenthe activity is over, reward your student by allowinghim to eat the cookies.

Tell your student that if he were a real ant, he wouldreturn to the colony and share the food he has eatenwith other ants. Ask him to look at an ant. How manystomachs does it appear to have? Explain that ants havetwo stomachs, one small and one large. The food thatgoes into the large stomach is shared with other mem-bers of the ant nest. Ask your student if he would wantto share some of the cookies he found, now that he hasalready eaten and swallowed them. Tell your studentthat sharing food is only one way that ants as well asbees demonstrate social behavior. Ask him why hethinks these insects are called social insects. (They liveand work together for the benefit of the entire colony.)

Bees and AntsText, pages 28-32

Notebook, pages 4-7

Preview


• 1 handkerchief or square of cloth for a blindfold.• 20 squares (2" x 2") of tissue paper.• 1 resealable plastic bag.• Perfume or vanilla extract.• Several cookies or other treat.• Bread crumbs or jelly.• Tiny pieces of banana and apple. *• Bits of walnuts. *• Ant farm prepared in Family Time 8.• Ants (different type from the ants in the ant farm) for

experiment on Day 4. *Prepare:

• The 20 pieces of tissue paper by placing a small dropofthe same perfume on each paper. (NOTE: Considerusing perfume, cologne, vanilla extract, or fruit-flavored extract.) Place the tissue papers into a re-sealable plastic bag to keep the scent strong.


Notice that each lesson begins with anactivity to stimulate your child's inter-est in science.

Direct a food-finding activity. Before the lesson be-gins, place several cookies or other treat in a hidingplace in the house. Leave a trail of scented tissue paperfrom the food to your student. Explain to him that you


name _

O~Hrw the Int linn for Oweday•. Anlwar tho following quosllons about the ant experiments andrecord your ob•• mltlonl carefully.

Ant Roles

1. Look for the queen ant. Is one present in the ant farm? _

2. Look for ant cocoons. Are there any present in the ant farm? If so, describe thecolor of the cocoons.

3. Look for winged ants. Are there any present in the ant farm? _

Ant Food

4. Did the ants eat the bread crumbs and jelly given to them on Day 11 _

5. Did the ants eat the pieces of banana and apple given to them on Day 31__

6. Did the ants eat the bits of walnuts given to them on Day 5? _

7. Which of the tested foods did the ants seem to like best? State your reasons.

Ant Activities

8. Observe an ant carrying food or digging a tunnel. Describe what you saw .

• 1990 Bob JO"" UnlV'r1lty Pren, ReproducUon prohibited,

D Sdence4_r •••••

LeSIonSTe.chlng the Uuon

Direct a Finding Out activity and a notebook activityon pages 4 and 5. Using the ant jar prepared in FamilyTime 8, instruct your student to observe the ants for fivedays. As your student makes his observations, he shouldrecord them on pages 4 and 5 of his notebook packet.

Day I Feed the ants bread and jelly. Remove any leftoverfood after 30 minutes. (NOTE: Mold grows quick-ly on leftover food.)

Day 2 Do not feed the ants.Day 3 Feed the ants tiny pieces of banana and apple.

Remove the food after 30 minutes.Day 4 Do not feed the ants. Instruct your student to ob-

serve the ants' response to "foreigners" by plac-ing 3 or 4 new ants in the jar. These ants shouldbe a different type of ant from those already in thejar.

Day 5 Feed the ants bits of walnuts. Remove the food asbefore.

Instruct your student to observe the ant farm care-fully for the next five days. Select 30 minutes in the daywhen the ant farm will be uncovered for observation.During this time follow the schedule above for feeding,watering, and adding of the "foreigners." Then allowyour student to record his observations on the notebookpage. Instruct him to be careful with the ant farm whilemaking his observations. He should never bump orshake the nest.

36

9. Observe the construction of the tunnels. Are most of the tunnels in view built

horizontally, vertically, or diagonally?

10. Observe one ant feeding another. Describe what you saw.

II. Observe two 'ants communicating with one another using their antennae.Describe what you saw.

12. Look for any dead ants. Describe what is done with their bodies,

13. Observe the reaction of the ants to "foreigners." Describe what you saw.

Sudden jolts frighten and excite theants, causing them to release formicacid. If the formic acid touches theirbodies, the ants may go into a frenzyand die of formic-acid poisoning.

SCIENCE 4 HTE

The Bee and An! GroupNearly everyone has dodged a bee or two, and many

have felt the burning sting when the dodge is not fastenough.

Only female bees have stingers. But all bees have twopairs of wings, the front wings being much larger than theback. The thorax and the abdomen of all bees arc distinctlydivided, sometimes seeming to be joined by a mere thread.

Bees are a well-organized group. They are hardworking, consistent, and efficient. Every bee has a job to doin the cotony, or community and it does it. The queen beelays eggs, making sure that the colony always has enoughworkers. The worker bees build the hive, make the hone).and take care of the eggs. The drones male bees thatmate with the queen.

'1 he worker bees have many skills. Ihcy are wonderfulbuilders. 'I hey not only make their own building materialsbut aha produce one or the nearest, most efficientstructures in nature. To store honey and protect the eggs.workers form thousands of six-sided cell-, out of wax. ThisWax comes out of the workers' abdomens. usually after thebees have eaten a lot 01 honey.

worker

drone

28

Teaching the LessonDirect a text activity on pages 28-32. Use the follow-ing questions to initiate your student's interest in whathe is going to read,1. What jobs do the worker bees have?2. How are bees good communicators?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Which bees have stingers? (female)2. What jobs do the worker bees have? (building the

hive, making the honey, and taking care of theeggs)

3, What jobs does the queen bee have? (lays eggs andmakes sure the colony always has enough workers)

4, How are bees good communicators? (When a beefinds a source of pollen or nectar, it returns to thehive and tells the other bees.)

5. How does a queen ant differ in its appearance fromother ants? (The queen ant has wings and isbigger.)

6, What are the body parts of the ant? (head, thorax,and abdomen)

7. How do the leafcutter ants divide their jobs? (ac-cording to the size of the worker)

Chapter 2: Lesson 8

The six-sided cells a bee hive arc so regular ill sil.cthat the width of a cell was once suggested as aninternational unit of measure. The <ix-sided shape makesthe best possible use of space and is the strongest furm thebees could use to support the hive.

The workers are also good hurvcsterx. They gatherpollen and nectar and carry il hack to the hlle in Iiulepockets on each hack leg called pollen ba-kers.

Bees can be good communicators. When a bee linds arich source of pollen or nectar. it returns to the hive anddoes a little "dance:' which actually terms a miniature map.The other bees learn "I he map." II hich take, into accountnot only direction but also time 01 day and disuuicc.

Perhaps 010:-.t important to LIS, the workers arc efficientsweet-makers. Bees make honey Irom the nectar the)collect. At first the sweet liquid is runny. hut the bees Ian itwith their \\ ings to make extra water evaporate. Then thehoney thickens. Where do IOU think we got the phrase

"busy as a bee"?

29

37

Another hard-working insect is the ant. Even the Biblecommends their industry. Ants look something like bees.although rarely do any but queen ants and the males havewings. The ants have distinct body segments: head, thorax,and abdomen. Many ants have no "stingers," but theirpowerful jaws can deliver it bite that may feel like a sting.

Like bees, ants divide up the work in their colonies. Theleafcutter ants, for example. have johs according to the sizeof the worker. The largest leafcutter ant is the queen. Herjob is to dig the first tunnel, lay the eggs. and begin acolony. Next in size are the soldier ants. big-headed, sharp-jawed insects that can kill enemy insects ten limes their sive.They guard the queen and the colony. Smaller ants, theworkers, give the whole group its name: they arc the onesthat actually cut leaves. This group goes out into anAnH\70n forest in long lines sometimes twelve-ants wide.They cut up leaves and carry the piece, home. From adistance these streams of ants, going and coming betweenforest and nest, look like littie conveyor belts in a very busyfactory.

31

Conclude the discussion. Explain to your student thata queen ant begins as a princess ant. She and her royalwinged-sisters and winged-brothers are fed and takencare of by the common female worker ants. In time, theroyal ants leave the old colony to begin new colonies.As they flyaway on their marriage flight, prince andprincess ants pair up together. When they return to theground, they go separate ways. The males will die in aday or two. However, each female (who has now be-come a queen) tears off her wings and begins digginginto the ground. She soon digs a small chamber just alittle larger than herself. Once inside she plugs the doortightly with dirt. Ask your student to think: of somereasons that the queen ant seals herself inside the cham-ber. (to protect herself/rom birds and other insects) Shewill remain in the chamber for weeks and even monthsuntil the young are born,

Point out to your student the verses at the bottom ofpage 32. Ask him whether he knows why Proverbs 6:6tells the lazy man to study the activities of the ant. Askyour student to list some lessons he could learn fromthe ant. (Answers will vary. Work together; use timewisely; use teamwork to tackle a difficult problem; etc.)(BAT: 2e Work)

38

To do the same amount of work as a lealcuuer, a ownwould have to run ten miles in forty minutes carrying all

800-pound weight over his head. And he would have to do

that at least seven limes a day.Back at the colony. smaller ants carry the pieces of leaf

down the many tunnels and give them to the smallest antsof all. These tiny insects about the size of an eyc in aregular sewing needle-chew up the leaves and use them togrow a fungus. All the ants in the colony cat this fungusand nothing else. Since a colony can contain as many asfour million ants, it is important that each ant do its job inthis process of growing food.

Some ants arc like little dairy farmers. They keep andfeed their "cows." the aphids. When stroked by the ants'feelers, the aphids give a sweet liquid. The ants need this"milk" and seem to do "chores" to get it."Go to rile (JIll, thou sluggord; consider her H'ays. and beH"ist': Which having NO gutdc. overseer, or ruler, Providethher meat ill the summer. and gathereth herfood in 'heharvest. " Proverbs 6:6-8

32

SCIENCE 4 HTE

name _

Us. your book and loday'. I•• ,on to mike a CO",p.lrlson IMtwM" beet and Ints. CompIeN theque,tlon, below with th, Inlormatlon you "nd.

Be es

I. Most beeO{dO) do not) have wings. •. ..

2. Most (mal~ bees have stingers. . ,"

3.~I Queen bees) have pollen baskets on their legs. ...•. ..

4. Worker bees are (male~.

5. List three jobs of worker bees.

build hive, make honey,

take care of eggs

6. List the jobs of the queen bee.

lay eggs, make sure that

the colony has enough workers

7. Bee((d.O:}'do not) communicate with one another.

8. Give one example to support your answer.

Bees communicate by dancing the directions

to a new source of pollen or nectar.

111M/) Bob Jones University Press. Aeproductlon prohibited.

D Sdence4Notebook Packet

Evaluating the LessonDirect a notebook activity on pages 6-7. Tell yourstudent that this evaluation involves comparing the bodystructures as well as the activities of bees and ants.Instruct him to use his book for this activity. Point outthat some parts of the notebook pages require him tocircle the correct answer, and other sections require himto write his response.

EnrichmentAn excellent addition to this lesson would be the

Moody Science video City of the Bees. This 28-minuteclassic takes the student on a visit to a beehive. City ofthe Bees can be ordered from Bob Jones UniversityPress.

For Your InformationThe ant's abdomen is called the gaster. Inside the

gaster are the ant's two stomachs. The small one belongsto the ant itself, but the other (the sac stomach) belongsto the entire colony. When a worker goes out to gather

Chapter 2: Lesson 8

6

Ants

9. Most ants (do~ have wings.

10. Most ants (do~ have stingers.

II. (Worker ants~ have wings.

12. Worker ants are (males~.

13. List three jobs of worker ants.

guard the queen and colony, cut up leaves

and carry the pieces home (gather food), and

chew up leaves and grow fungi

14. List the jobs of the queen ant.

dig the first tunnel, lay eggs,

and begin a colony

15. Ants~do not) communicate with one another.

16. Give one example to support your answer.

Ants communicate by leaving an odor trail

telling where food can be found.

food, it extracts any juices from the solid food it finds.These juices are then swallowed, but the rest is spit out.When the field worker returns to the nest, it will shareits food with other worker ants who in turn will sharewith larvae, queens, or other workers.

Ants lay odor trails by dragging their abdomensalong the ground and releasing formic acid. Odor trailsare usually not necessary if the food supply is locatednear the nest. In this case the ants recruit helpers bycommunicating with their antennae. However, if thefood supply is some distance from the colony, an odortrail is necessary. Each ant who follows the trail to thefood will also follow the trail to find its way back home.As long as there is still a large amount of food to begathered, each returning ant lays its own odor trail ontop of the previous one, keeping the odor strong. Thestrength of the odor communicates to the ants that manymore workers are needed to gather the food. As the foodsupply dwindles, fewer ants lay down a new scent trailon their return trip home. Eventually the ants gather thelast of the food, returning home on the faint odor trail.Soon the remainder of the formic acid breaks down, andthe obsolete trail disappears.

39

Lesson 9IdentifyingInsectsText, pages 33-34

Notebook, pages 8-11

PreviewObjectives


• Group insects according to the number and structureof their wings.

• Use a simple classification key.


• 5 insects in resealable plastic bags.• I small magnifying glass (optional).*t• 5 insect pins (optional).* (NOTE: Number 3 insectpins work well for average-sized insects. Insect pinsare recommended because of their slenderness andextra length, but straight pins may be substituted.)

• I toothpick.• Small section of cardboard (about 3" x 3") (optional).• Viewing jars and boxes (optional).• A Write It flip chart.

NotesThe following is a list of choices of how the insects

in this lesson may be handled when your student hascompleted the classification process.1. Your student may return the insect to its resealable

plastic bag.2. Your student may make a permanent collection

using viewing jars and boxes. Clear plastic nuts-and-bolts organizers make great viewing boxes.The organizers have individual sections to keep theinsects separated, and mounting the insects is notnecessary. Viewing jars can be constructed byscrewing a strip of wood (1" x T") into the lid.The length of the wood strip must be cut to fitinside the jar. Mount the insects to either side ofthe board and place them in the jar. Place a fewmoth crystals in the bottom of the jar to preservethe insects.

40

About InsectsI. Get a plastic margarine container with a lid and five

scalable sandwich bags.

2. Catch an insect in the container and then put it into asandwich bag. Without crushing the insect. to keepits wings spread. Catch and at least insects thisway. Try to get insects that look different from eachother as possible.

3. Put the bags into the freezer for an hour

4. Bring your insects to class in the bags. With yourteacher's help. classify and mount your insects.

5. Display your mounted insects with those of yourclassmates.

34

3. Your student may mount the insects on cardboardby using insect pins. Show him Figure 9-1 whichgives the proper place that the pins should be in-serted. The pin should pass through the center ofthe insect's thorax, just behind its head. Instructyour student to place insects right side up on thecardboard carefully. Then insert one of the pinsthrough the insect and into the cardboard. Yourchild may have difficulty pinning the heavier ar-mored beetles.


1. Set up the Finding Out activity on page 34. Yourstudent should get a toothpick and the insects that hehas collected. (NOTE: The number of insects may beadjusted to correspond with lesson time.) Tell your stu-dent to number his insect bags with a pen.2. Introduce the classification key. Point out the clas-sification key on notebook pages 8-9. Read the direc-tions and tell your student that some insect groups willoccur more than once in the key. For example, a cricketand a walking stick are both insects that belong in thegrasshopper group; however, one has no wings and the

SCIENCE 4 HTE

name _

6a. Are the front (top) wings SIMILAR in size and shapeto the back (bottom) wings?• If yes, the insect is in the Dragonfly group.o If no, go to 6b.

UI' the following simple cl ••• ltlc.tlon key while studying your Intecll. The key I, mtIde up ofque,tlona which d.,crlbe different lneeet wing •• Follow the direction. below each que,tlon. Recordyour progr ••• through the key In the Ipace provlded.t the end. Continue re.dlng the qu •• tkml Mdfollowing the direction. until you find the proper group for your Insect. Record your findings In ••••,plce provided on peg •• 10 and 11.

I. Does the insect have wings?o If yes, go to 2a.o If no, the insect could be in the Flea group, Aphid

group, Bee and Ant group, or Grasshopper group.

6b. Are the front (top) wings DIFFER£NTin size andshape from the back (bottom) wings?• If yes, the insect is in the Bee and Ant group.

~

~H

7a. Do the tips of the front (top) wings overlap? (SeeFigure 9-2.) AN () are the front (top) wings slightlythicker at the base'!• If yes, the insect is in the Bug group.• If no, go to 7b.

2a. Does the insect have ONE pair of wings?• If yes, the insect is in the Fly and Mosquito group.o If no, go to 2b.

2b. Does the insect have TWO pairs of wings?o If yes, go to 3. 7b. Does more than the tips of the front (lop) wings

overlap? AN!) are the front (top) wings NOT thicker at3. Are the front (top) pair of wings thin and transparent?

o If yes, go to 4.o If no, go to 8.

the base?• If yes, the insect is in the Grasshopper group.

8. Are the back (bottom) wings thin and transparent?• If yes, go to 9a.• If no, the insect is in the Moth and Butterfly group.

4. Do the wings form a peak over the body? (See Figure9-1.)

• If yes, the insect is in the Aphid group or theGrasshopper group. (Note: If the last pair of legs are much

larger than the rest, it belongs in the Grasshopper group.)

• If no, go to Sa.

9a. Do the front (top) wings lie flat against the body,meeting in a straight line along the back?• If yes, the insect is in the Beetle group.• If no, go to 9b. M

~FIgure 9-3

Sa. Do the front (top) and back (bottom) wings lie flatagainst the body? AND are the back (bottom) wingshidden from view even when you turn the insect upsidedown? (Note: The tips of the back (bouorn) wings may be visible.I

• If yes, go to 7a.o If no, go to 5b.

5b. Are the front (top) and back (bottom) wings held awayfrom the body? AND can you see the entire back(bottom) wings when you turn the insect upside down?• If yes, go to 6a.

9b. Do the front (top) wings form a peak over the body?(See Figure 9-3.)• If yes, the insect is in the Aphid group.

D Sdence4Notebook PAcket

Leason 9

TNChlng In. Leuon

other has two pair of wings, Tell him that most insectshave two pair of wings. However, sometimes one pairis hidden from view. For this reason it is important thatyour student study each insect carefully, Through hisstudy he will discover that there are many kinds of insectwings, ranging from hard, thick, shell-like wings to thin,transparent wings that look like plastic wrap, (NOTE:You may need to point out to your student that the thick,shell-like coverings of certain insects are wings.)3. Review terms and demonstrate the key. Explainthat the term transparent means that you can seethrough the wings, If your student is not sure whetheran insect's wings are transparent, a good test is to slipunderneath one of the wings a piece of paper with writ-ing, The words should be clearly visible if the wingsare transparent. The wings of butterflies and moths arescaly and usually not transparent. The wings can be-come transparent, however, if they are handled toomuch and the scales are rubbed off, Warn your studentto handle butterflies and moths carefully, Bare spotscould affect the results of the key. Demonstrate how thekey works by taking one insect and going through thekey with your student and answering any questions thathe may have,

Figure 9-1

41Chapter 2: Lesson 9

name _

Record your ftndInp here.

Insect I: Used key numbers _

Insect Group _

Insect 2: Used key numbers _

Insect Group _

Insect 3: Used key numbers ....:...- _

Insect Group _


Insect Group _

Insect 5; Used key numbers _

Insect Group --' _


Insect Group _

01990SobJont,Univi!rsityPres5 Reproduc1ionpfohibiled

D Sdence4~,adIet

Teacher information for the classification key.

Beetle group: Members of this group have two pairof wings. The front pair of wings may be hard andshell-like (often shiny), or they may be leathery. Thefront wings nearly always meet in a straight line alongthe back. Back wings are thin and membranous andare usually longer and folded under front wings.Grasshopper group: Members of this group usuallyhave two pair of wings, or they may have no wingsat all. (Few have only one pair of wings.) The frontpair of wings feels like heavy paper, and the backpair of wings is membranous and usually folded fan-like underneath the front pair. Roaches belong to thisgroup.Bug group: Members of this group have two pair ofwings. The front pair of wings are slightly thickerwhere they join the body and thinner toward the end.The tips of the front wings overlap. Back wings aremembranous and shorter than the front wings.Aphid group: Members of this group may have twopair of wings, or they may be wingless. The frontwings are usually thin and transparent, but some spe-cies have thickened wings. The wings usually forma tentlike peak over the body. The back wings aremembranous and shorter than the front wings.Dragonfly group: Members of this group have twopair of long, membranous, many-veined wings. Thefront wings and back wings are similar in size and

42

10


Insect Group _


Insect Group _


Insect Group _


Insect Group _

II

shape. The abdomens of dragonflies and damselfliesare long and slender, and their eyes are quite large.Flea group: Members of this group are small (lessthan 5 rum), wingless insects. Fleas have somewhatflat, bristly bodies with relatively long legs.Moth and butterfly group: Members of this grouphave two pair of wings that are mostly covered withscales. When rubbed with a finger, the scales appearas a colorful, powdery residue.Fly and mosquito group: This group has only onepair of membranous wings. The insects in this groupusually have large eyes.Bee and ant group: Members in this group may havetwo pair of wings or may be wingless. The wings aremembranous, with the front wings being a little largerthan the back wings.(NOTE: A large number of the orders include a va-riety of insects without wings. These groups includethe butterflies and moths, bugs, and beetles. Thesegroups are not included in Question 1 of the keybecause these examples are rare. You should also beaware that the classification key used by your studentis a modified version of a true classification key. Thekey was specifically adapted for use by elementarystudents. An example of a true classification key willbe used in Lesson 45 with tree leaves.)

SCIENCE 4 HTE

4. Oversee your student's observations. Tell him touse the key to guide his observations. In order to findthe number or structure of the wings, he may need touse a toothpick to lift and gently separate the wings.Instruct your student to study carefully the structure ofthe insects' wings.

To keep track of his progress through the key, in-struct your student to mark lightly with a pencil eachquestion he used. When he has finished keying eachinsect, he should record the numbers of the questionshe used as well as the insect group in the space providedat the end of the key. He should then erase his marksand repeat the activity for the next insects.

Tell your student that the classification key he usedfor his insects is a simple one and has its limitations.Point out that the key covers only the nine insect groupsdiscussed in his book. Ask him how many insect groupsthere are. (26) It is likely that he will find an insectwhose group is not mentioned in the key. Also pointout that his key uses only the study of insect wings.Remind him that scientists actually use many character-istics (wing structure, mouth parts, type of metamor-phosis, etc.) to identify insects. For this reason theremay be some insects that are placed in the wrong group.

Although this activity will likely resultin some insects' being improperlyidentified, the goal is to give your childsome exposure to using a classificationkey. The emphasis of this activity is toencourage him to make his own deci-sions based on personal observationsand not on field guides he consults toidentify an insect.

5. Conclude the activity. Tell your student to look athis insect collection. Remind him that scientists haveidentified 800,000 different kinds of insects. Ask himto study the many ways the insects differ. Ask yourstudent who he thinks is responsible for all this variety.(Bible Promise: I. God as Master) Allow him to expresssome ways he has seen God's creation at work whilestudying insects.6. Clean up. Since this activity involves handling deadinsects, schedule enough time after the lesson for youand your student to wash your hands thoroughly.

Chapter 2: Lesson 9

The Flea GroupThe fleas have a group name, Siphonaptera. that means

"siphon without wings." What can you guess about theflea's mouth? What can you guess about how the flea getsaround?

Fleas have sucking tubes for eating and legs designedfor leaping. One kind of flea can jump thirteen inches inone jump. You probably think fleas are the pests on dogs.But fleas feast on many hosts. including people. And theyhop from one host to another at any opportunity.

Although the flea is a small animal, it has carried deathto millions, In the 900s, fleas from sick rats spread a plagueknown as the Black Death throughout Asia and Europe.The plague wiped out one-fourth of the population ofEurope. In the late 1800s, another pandemic began whenships from Hong Kong traveled to many ports around theworld with diseased rats aboard. In India alone, 10,000,000people died within twenty years,

33

Teaching the LessonDirect a text activity on page 33. Use the followingquestion to initiate your student's interest in what he isgoing to read: How do fleas feed?Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. How do fleas feed? (They have sucking tubes for

eating.)2. How far can some fleas jump? (thirteen inches)3. What is the Black Death? (a deadly plague spread

by fleas)

43

Evaluating the LessonDirect a guessing game. Begin the activity by listingthe following insects on the Write It flip chart: ladybug,praying mantis, stinkbug, cricket, fly, ant, bee, dragon-fty, ftea, butterfly, and aphid. Tell your student to selectone insect and keep the choice secret. He should writea description about his insect, using the same style as aringmaster introducing the mystery star of a circusshow. His description should include five clues aboutthe insect without giving the insect's name, and theclues should become increasingly obvious.

Allow him some preparation time; then ask yourstudent to present his descriptions, pausing after eachclue. You should listen to the clues and try to guess theinsect in the description. After you have guessed hisinsect, prepare an insect description for your student toguess. You may play the game for as long as you feelyou have time.

For Your InformationBlack plague (or bubonic plague) spreads from rat

to flea to man. When a flea feeds on the blood of aninfected rat, it sucks in the bacteria for the disease aswell. The bacteria now infect the flea, and it becomessick too. In the flea's stomach the bacteria begin tomultiply until the flea is so clogged with the bacteriathat it can hardly suck blood. After the flea does suckup a little blood, it regurgitates the blood along with thebacteria. The bacteria enter the host's body through thewound made by the flea. In time the flea dies, but notbefore giving the plague to its host. As more rats be-come infected and die, the number of rat hosts decreas-es. The fleas find an alternative host-the human be-ing-and pass on the deadly bacteria.

44 SCIENCE 4 HTE

Lesson 10Arachnids andMyriapods

Text, pages 35-38

PreviewObjectives


• Identify those characteristics that make spiders dif-ferent from other arthropods.

• Distinguish between insects and spiders.


• Home Teacher Packet, p. 7.• Spider's web.*• 1 ball of yam.


You will want to find a spider's webbefore teaching this lesson. You maytry looking in comers, especially ofrooms that are not used frequently. Inthe early morning you can find webson bushes when the dew is shining onthem. You may want to leave the webin its original location and introducethis lesson in front of the web.

Observing a spider's web. Allow your student sometime to study and to watch the spider and the web. Usethe following questions and statements to guide him inhis observations.

1. What does the web look like or what does it remindyou of? (Your student's answer will vary. If theweb looks like bicycle wheels, you can tell him thatit is called an orb web.)

Chapter 2: Lesson 10

2. Where is the spider waiting for a meal? (Somespiders hide off to the side of their web with onefoot touching an alarm thread; other spiders waitin the center, or hub.) When an insect gets caughtin the sticky silk, the spider feels the movement ofthe struggling insect in its web. Those vibrationsalso allow the spider to locate its prey quickly onthe web.

3. Ask your student to blow on the web. Did thespider move? (no) Does the spider move when aninsect gets trapped in the web? (yes) Explain toyour student that God has created the spider withthe ability to tell the difference between move-ments made by wind and movements made by atrapped insect.

4. What would happen if the spider ran out of hidingfor every little movement of its web? (It wouldwaste a lot of its time and energy.)

5. If your student observed an insect being caught bythe web, you can ask him what the spider did whenit reached the insect. (It covered the insect withsilk.)

6. Usually when a spider catches an insect in its web,it first wraps the insect like a mummy in silk andthen thrusts its deadly fangs into the insect. Canyou see any benefits of this method when the spidercatches an insect like a bee or wasp in its web?(The bee cannot move and sting the spider.)(NOTE: Spiders bite moths and butterflies first,because there is not enough time to wrap them insilk. When a moth gets caught in a web, the scaleson its wings stick to the web. But as the moth triesto escape, the scales pull away from its body, free-ing the moth from the web.)

45

The ArachnidsThe ancient Greeks had a story about a beautiful girl

who could weave better than anyone else. One day shechallenged the goddess Athena to a weaving contest.Athena was outraged that a mere mortal would claim to beas good a weaver as she, In anger. she changed the girl intoa spider. The girl's name was Arachne, and her namebecame the name for arthropods in the spider classarachnids. Why do you think spiders were named after her"

Spiders, scorpions, daddy longlegs, and ticks all hawcommon characteristics. Like all arthropods they have anexoskeleton and jointed appendages. But they also havequalities that make them distinct from other arthropods.

How does a spider look different frum an ant?Arachnids have four pairs of legs. The head and thorax of aspider arc joined. seeming to be one part. How IS the antdifferent in structure" Why is a spider not an insect"

Arachnids do not have antennae. Spiders do, however.have two pair; of appendages all their heads. for poisoningand holding their victims. Do arachnids have wings?

35

Teaching the LessonDirect a text activity on pages 35-38. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. What are the characteristics of spiders?2. How do spiders get their food?3. What is a myriapod?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Look at the spider pictured on page 35, Count the

number of legs. (eight) The structures that looklike an extra pair of short front legs are calledpedipalps. (NOTE: See Figure 10-1.) Spiders usetheir pedipalps for holding their prey, not forwalking.

2. How many body divisions can you count? (two)Does the spider have a separate head? (No, it iscombined with the thorax, the middle section foundin insects.i This is called a cephalothorax. Cephalomeans "head,"

3. Study the picture once more. Do you see any wingsor antennae? (no)

4. How do spiders get their food? (build webs, usetricks or traps, and go fishing)

46

Spiders are the most misunderstood of arthropods.K tiled on sight many times, they are actually helpful toman. They feed mostly on insects, controlling pests.

Spiders get.their food in many different ways. Many, of

course. build webs. Although one strand of a cobweb maylook fragile. it is surprisingly strong. A web needs 10 bestrong-it is the spider's home. Very large insects that getcaught in a sticky web cannot usually struggle free. Evenhummingbirds have gotten tangled fast in the sturdy snaresof spiders' webs. One study showed that if you could makea rope of web one inch thick it could hold up seventy tons!

Other spiders, however, use other tricks and traps. Thetrapdoor spider digs a hole in the ground and builds a doorover it. The spider lurks under the partially open door.When an insect goes too near the door, the spicier lungesout and grabs it.

36

Figure 10-1cephalothorax abdomen

Spider

SCIENCE 4 HTE

Another kind of spider sometimes goes fishing. Itperches on a plant near a stream or pond. occasionallydangling a leg in the water to attract fish. If a fish comesup. the spider waits until it near the surface and thenjumps on it. Sinking his fang-like pinchers into it. thespider d rags his catch ashore to eat it.

Two kinds of poisonous spiders arc the brown recluseand the black widow. The brown recluse alwavs has aviolin-shaped yellow spot on il> bad. The black widow hasyellow to red splotches that sometimes resemble anhourglass on the underside of its abdomen. Both spiderscan inflict painful bites that cause vomiting. fever. musclecramps. and sometimes death.

37

5. Why do you think that the trapdoor spider con-structs its trapdoor with the same material as itssurroundings? (Your student's answer will vary. Itmakes it harder for the spider's enemies to find itshome, and it keeps the presence of the spider asurprise.)

6. Name two kinds of poisonous spiders. (brown re-cluse and the black widow)

7. Look at the animals pictured on page 38. Are theyspiders? (no)

8. List some characteristics that spiders have that arelacking on these animals. (eight legs, two bodysegments, no antennae)

9. Are these animals insects? (no) List some charac-teristics that distinguish insects from these animals.(Insects have six legs and three body parts.)

10. What are the two animals pictured on the page?(scorpion and millipede)

1L What does the word myriapod mean? (Myriadmeans "many" and pod means "foot," Myriapodmeans "many feet.") What are two animals in thisgroup? (centipedes and millipedes)


The scorpion has legs like a spider. but it also bas along. narrow abdomen that has pinchers and a stinger atthe end. The stinger puts poison into the spiders and insectsthat the scorpion catches, If it stings a human. the scorpioncan cause a painful swelling but it rarely can kill. Can youfind scorpions mentioned in the Bible?

The daddy longlegs looks like a tall, spindly spider. Iteats insects such as plant lice. Who should especially likethe daddy longlcgs?

The Myriapods

47

The word myriad means "many": pod means "foot."What do you think the name niyriapod tells about themembers of this group'?

Centipedes and millipedes are myriapods. These arelong. thin creatures with many body segments. Centummeans "hundred" and mille means "thousand." Pede andpod come from the same word. Which rnyriapod has morelegs')

38

If your child needs additional review,instruct him to flip through the previ-ous pages (18-34) in the chapter andlook briefly at the insects picturedthere. This review should help him tosee the differences between spidersand insects now that he has studiedthem.

Conclude the discussion. Display page 7 of the HomeTeacher Packet, showing several different spider heads.Point out the special jaws with the pointed fangs. Tellyour student that spiders use fangs to poison their prey.Ask him to count the number of eyes on the differentheads. Tell him that most spiders have eight eyes, butsome have six, and a few that live underground have noeyes. Ask him whether he thinks spiders have goodvision. Explain to your student that many web-weavingspiders actually have poor vision; they depend on theirsense of touch to find their prey.

Evaluating the LessonDirect a spider web activity. Tell your student to geta sheet of paper and list at least ten different things hehas learned about spiders in today's lesson. Encouragehim to list more than ten if possible. Tell him that todayhe will "spin" his own spider web. Explain that youwill begin by tying the end of a ball of yam to yourchair. He should take the ball of yarn and tie it to adifferent chair or piece of furniture. Each time he tiesthe yarn ask him to give you one fact about spiders.(NOTE: Choosing furniture on opposite sides of theroom will produce a more tangled web.) By the time hehas had an opportunity to list his facts, he should beentangled in a giant cobweb. Ask him if his web lookslike a wheel. (no) Tell him that a lot of webs do nothave a specific shape; they are a tangle of silk, like theone he just created. The house spider, for example,weaves a tangled web often seen in attics and cellars.

EnrichmentProvide a copy of Charlotte's Web (a popular story

about a spider) by E. B. White, or take a personal visitto see the spider by showing the Eight-Legged Engineer.This ten-minute adventure is one of three included inthe Moody Science video Treasure Hunt, which can beordered from Bob Jones University Press.

For Your InformationA spider may have five or six different types of silk

glands that produce different silk for different purposes.Strong threads are needed to make the framework for aweb. Another kind of gland makes sticky threads forthe spiral part of the web. A different gland makes theextra strong threads needed for draglines. The draglinesilk supports the spider as it hangs. Even finer threadsare used to tie up a captured insect or to insulate an eggcase.

Only spiders have spinnerets. (NOTE: See Figure10-1.) These structures are located at the back of theabdomen. The liquid silk is made by glands in the ab-domen. Different silk glands connect to each spinneret.As the spider pulls out the thick liquid silk, it hardens.

Scientists are experimenting with some special usesfor spider silk. They believe that some day the materialwill be used in heart valves, artificial veins, and othersurgical implants. Other scientists are trying to copy thestrong fiber with the idea of producing a lighter, morecomfortable bulletproof vest than those that policemencurrently wear.

48 SCIENCE 4 HTE

CHAPTER

3Electricity

[ll]Lessons 11-14

[ll] Electricity

39


This chapter highlights the importance of electricity ineveryday life. It explains basic electric theory: what createsit and how man harnesses it. Lessons 12 and 13 presentthe differences between static and current electricity, andin Lesson 14 your student wi\l see the way electricity andmagnetism work together.



* An old orange, cantaloupe, or lemon (Family Time13)

* Compass] (Lesson 13)* 7 feet of #20, #22, or #24 insulated copper wire+ (Les-

son 13)* 1 glass or ceramic insulator from a telephone or elec-

trical wire (optional) (Lesson 13)* 1 pair of wire cutters (Lessons 13 and 14)* 1 dry-cell battery (l.5 volt)'] (Lessons 13 and 14)* 1 knife switch] (Lessons 13 and 14)* 16 + feet of #20, #22, or #24 insulated copper wire]

(Lesson 14)* 1 iron bolt or rod between 4" and 6" long (Lesson

14)* 1 bar magnet+ (Lesson 14)* Iron filings] (Lesson 14)

49

Lesson 11Making

ElectricityWork

Direct an observing activity. Darken the room. Ex-plain that rubbing the balloon with the wool will givethe balloon many more electrons. Tell your student thathe will learn about electrons in this lesson. Rub theballoon with the wool for 15 to 30 seconds. Then, usingthe string, pull the balloon away from the wool, makingsure that the balloon does not touch anything. (Doingso may be difficult since it will be attracted to anythingclose to it.) Allow your student to touch the balloonwith the tip of his finger. A spark should fly betweenhis finger and the balloon. Ask him what this sparkreminds him of. (lightning) Tell him that in this lessonhe will learn what causes lightning and this spark.

Text, pages 40-42Notebook, page 12 If you have trouble getting a spark, rub

the balloon with the wool again andtry bringing the balloon close to a wall.After the balloon comes in contactwith the wall, pull it back and haveyour child touch it again.

PreviewObjective


• Determine whether two objects will cause a shock ora spark.


• Home Teacher Packet, p. 8.• 1 balloon.• 20 inches of string.• 1 wool sweater, scarf, or pair of gloves.

Prepare:• The balloon by inflating it and tying it off with string.


Direct a discussion on the importance of electricity.Ask your student to name some electrical appliancesthat he uses each morning. (Answers will vary.) Askhim how he would get ready in the morning if he didnot have electricity. (Answers will vary.) Ask him toname everything in the room that uses electricity. (An-swers will vary.)

This observation activity works beston a cool, dry day. It would probablybe best to try the experiment beforeyour lesson to make sure that the air isdry enough.

50 SCIENCE 4 HTE

Electricity is a mystery. No one has ever observed it orheard it or felt it. We can see and hear and feci onlv whatelectricity does. We know that it makes light bulbs 'shineand irons heat up and telephones ring. But we cannot saywhat electricity itself is like.

\Vc cannot even say \\ here electricity comes from. Somescientists think that the sun may be the source uf mostelectricity. Others think that the movement of the earthproduces some or it. All anyone knows is that electricityseems to be everywhere and that there are many ways tobring it forth.

How would you have to change the way you get readyfor school if you did not use clectricitv?"The voice of !II)' thunder uc.v in (he heaven: the lighlJ/;'1XSlightened the world: the earth trembled and shook:"

Psalm 77:18

40

Teaching the LessonDirect a text activity on pages 40-42. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. Where does electricity come from?2. What are the three parts of an atom?3. What does electrically neutral mean?

Continue with discussion questions. After your stu-dent ~ompletes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Can you see electricity? (no) Where does electric-

ity come from? (No one knows for sure.)2. Describe a static shock you have gotten. (Answers

will vary.)3. What causes static electricity to jump from one

place to another place? (the activity in the atom)4. What is an atom? (Answers will vary.) Explain that

everything is made of atoms. Atoms are like analphabet for our universe: just as several differentletters make up all our words, several differenttypes of atoms make up our universe.

5. What are the three parts of an atom? (protons.neutrons. and electrons) The electrons have a neg-ative charge; the protons, a positive charge; andthe neutrons, no charge.

Atoms have three pans. In the center are protons andneutrons. Whirling around that Center arc electrons. Anatom has as many electrons as it has proton". It is inbalance: that is, it is electrically neutral. To make electricityact, the number of electrons and proton, must beunbalanced.

The oldest method or making electricity is to rub twoobjects together. The ancient Greeks found that amber. astone 01 petrified sap. sparked \I hell it was rubbed with fur.Their word for amber WH!o\ elektron. How b our wordelectricit v like that word"

6. Which two parts of the atom are bound together toform the center (the nucleus)? (neutrons andprotons)

7. How do you think an atom is like our solar system?(The electrons whirl around the protons and neu-trons in a way similar to the way the planets travelaround the sun.) An atom is also like the solarsystem because it is mostly empty space. If an atomwere two miles in diameter, the nucleus (in thecenter) would be the size of a tennis ball, and theelectron (on the edge) would be smaller than agrain of sand. The space between the nucleus andthe electron is empty.

8. Look at the diagram on page 42. Count the numberof electrons (the circles with the negative sign).(eleven) How many protons are in the nucleus?(eleven) What can we say about this sodium atom?(It is in balance or electrically neutral.)

9. To make electricity act, the number of electronsand protons must be unbalanced. How do you thinkthis works? (Answers will vary. In an electricalflow, some atoms have fewer electrons than otheratoms. When this happens. the electrons are out ofbalance with the protons. When these electrons tryto get back in balance. an electrical current iscreated.)

51Chapter 3: Lesson 11

10. Remember the spark you saw between your fingerand the balloon at the beginning of the lesson. Howis this spark similar to lightning? (The spark wascaused by an exchange of electrons, similar tolightning.)

11. Display the picture of the clouds on page 8 of theHome Teacher Packet. What do these clouds andthe balloon from our demonstration have in com-mon? (Both have unbalanced charges. Both haveelectrons that are out of balance, and that is whatcauses the lightning and the shock.)

12. How is the Greek word elektron similar to ourword electricity? (Our word comes from the Greekword; they sound alike; they both have to do withbringing forth energy.)

Conclude the discussion. Ask your student what hethinks makes atoms stay together. (Answers will vary.)Tell him that scientists have many ideas but do not knowfor sure because nobody has ever seen inside an atom.Then read Colossians 1:16-17. Everything is held to-gether by the power of Christ Jesus. Without His pre-serving power, the universe would fly apart. While thosewho are unsaved struggle to find out why atoms staytogether, we as Christians know that God does it. (BiblePromise: I. God as Master)

52

name _

Write yes In the blank if there will be an eleclrtcallhock. Write no II there will not.

yes

On a warm, rainy day

± ± ±± + ±± ±- ± ± ± ±

yesno

etsso aoe rooes Un;v(!rsilyPress.Reproduc1ionprohibited.


tesecn trEvaluating the lHson

Evaluating the LessonDirect a notehook activity on page 12. Guide yourstudent as he completes the page.

For Your InformationMany experiments demonstrating static electricity

will not work on humid days. In damp weather theelectricity or charge stored in the object leaks too easilyinto the air around it. In dry weather, the air does notconduct electricity well; therefore, the static charge isbuilt up in the object.

In the past several years, many scientists have begunto doubt the long-held theories about atomic structure.Although the theories work, most of them are based onguesswork. Some of them even contradict the laws ofbasic science.

For example, most models portray atoms as havinga nucleus made up of protons and neutrons bound tightlytogether. However, if the nucleus followed the laws ofelectricity, the protons would repel each other, and the

SCIENCE 4 HTE

12

nucleus would fiy apart. Physicists have developed atheory of a strong nuclear force to account for the ex-istence of the nucleus. The theory holds that the nucleusis bound together by this force, a force that applies toall the particles of the nucleus. Although most of nuclearscience is theoretical, the theories work. And as long asthey work, scientists will continue to use them.


Lesson 12Static

ElectricityText, pages 43-47


Materials

PreviewObjectives

Have available:• 2 balloons.• String.• I wool sweater or pair of wool gloves.


• Determine an atom's charge.• Determine whether two charged atoms will repel or

attract each other.

54 SCIENCE 4 HTE

About Static Electricity

I. Get two balloons, some string, and a wool sweater orgloves.

2. Blow up the balloons and tie each with a length ofstring. Rub one of the balloons several times on thesweater or with the gloves.

3. Hold the other balloon by the string and bring it nearthe balloon you just rubbed. What happens"

4. Now rub the other balloon with the wool. Holding bothballoons by the strings, bring them close together.What happens?

5. Record your observations.

47


Direct a Finding Out activity on page 47 and note-book page 13. Ask your student to read the activitysilently before he begins, Instruct him to blow up theballoons and to tie them with a piece of string. Allowhim to rub one of his balloons with the wool sweater orgloves for about thirty seconds. Instruct him to holdeach balloon by the string. The balloons should be at-tracted to each other. Tell him to try to pull the balloonthat he rubbed away from the other balloon. The balloonshould follow. Ask your student why the balloons areattracted to each other. (The balloon that was rubbedagainst the wool gained electrons from the wool andtherefore gained a negative charge, while the other bal-loon remained neutral. The negative balloon is attractedto the neutral balloon.)

Next, tell your student to rub both balloons with thewool and hold them both by the string. Instruct him tobring the balloons close together. Ask him why theballoons repel each other. (Both balloons have a nega-tive charge; like charges repe/.) Instruct your studentto answer the questions and record his results on note-book page 13.


name _

I. What happens when you hold one balloon by its stringnear the balloon you just rubbed?

The balloon on the string Is

attracted to the balloon

in my hand.

2. What happens when you rub both balloons. hold bothby the strings, and bring them close together?

They repel each other.

3. Rub one of the balloons again and hold it by the string.See what happens when you hold it near objects aroundthe room such as the wall, your hair, or your clothes.Record the objects and results below.

Object

D Sdence4_.odd

Result

.1I!QnR<-lh.'M •• UnIY.rlllyP, ••• , RcproduoUon prohibited.

L••• on 12

IntfoduclnglheLetlon 13

55

When two objects rub together, some of the electronsfrom one go oyer to the other. The balance of electrons inboth objects is now disrupted. The objects arc charged. Ifan object has more electrons than protons, it has a minuscharge. If it has fewer electrons than protons, it has a pill>charge.

When you walk across a carpet. your body gathers extraelectrons. Do you have a minus charge or a plus charge?When you touch a metal knob, the electrons "jump" fromyour hand to the knob. You feci a sting and hear a snap.The electricity is then, we say. grounded.

Lightning flares in the sky for the same reason. Dropsof water rub against the air in the clouds. Large dropsalways plus-charged -fall toward the bottom of the clouds.The smaller. minus-charged drops stay higher in the clouds.For a while, the air keep' the different charges apart, orinsulates them. But when it no longer can, the electricityjumps across the cloud or between clouds in a giant spark:lightning. We call the sound of that exchange thunder.

43

Teaching the LessonDirect a text activity on pages 43-46. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. What would happen if two atoms that had a neg-

ative charge ran into each other?2. What causes lightning?3. What is St. Elmo's fire?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Have you ever gotten shocked after walking on

carpet? (Answers will vary.) Why do you think yougot shocked? (His body had gained a minus ornegative charge; so the extra electrons jumpedfrom him to the thing he touched.)

Explain to your child that the term mi-nus charge is the same as negativecharge and that plus charge is the sameas positive charge.

56

I

rSometimes the spark goes between the cloud and the

earth. Why are tall buildings nr the highest points in flatareas most likely to be hit?

Do you know a way that people try to make lightningtravel into the earth. that is. to be grounded') They putlightning rods on tops of buildings. A heavy wire runs fromthe rod down the side 01 the building and onto a metalplate in the ground. If lightning strikes the rod. the wirecarries the electricity into the ground.

44

2, What causes a negative charge? (when an objector an atom has more electrons than protons) Whatcauses a positive charge? (when an object or anatom has more protons than electrons)

3. Unlike charges attract and like charges repel. Whenan atom has more electrons than protons, it has anegative charge; when it has more protons thanelectrons, it has a positive charge. What wouldhappen if two atoms that had a negative charge raninto each other? (They would repel.) What if twoatoms that had a positive charge met? (They toowould repel.) What would happen if one atom witha negative charge came close to an atom that hada positive charge? (They would stick together.)

4. Do you remember the experiment Benjamin Frank-lin did to show that the force that makes lightningis electricity? (He tied a key to the string of a kiteand flew it in a thunderstorm. He attached the keyto a jar that would store electricity.)

Emphasize that Franklin was fortunatethat he did not get hurt. Tell your childthat he should never try to copy Frank-lin's experiment. Many people havebeen killed by trying to perform thissame experiment.

SCIENCE 4 HTE

Sometimes at night, in tall ship, a dim glowwavering at the tops of the masts and at the ends of polesthat hold the Heron: sailors understood that the lightwas caused by static passing from the ship intothe air, they called it Sf 'sfire. Imagine ho« nmust have seemed to men whoto see the top of their mast;

nothing of electricityin the dark. but

burning or smoking.Thunder and lightning and St. Elmo's fire all result

from the action of stauc electricity. Why do you think St.Elmo's fire is quiet glo\v and thunderstorm!lashes)

45

5. What causes lightning? (One part of the sky hasmore electrons than the other; lightning is the ex-change of these electrons.) Ask your student toread Job 37:3 aloud. Tell him that only God hasthe power to keep forces such as lightning undercontrol and that He does so in His sovereignty.(Bible Promise: 1. God as Master)

6. Why is lightning more likely to hit tall buildingsor high points of land? (The lightning finds theshortest way to the ground, and it will follow thepath of least resistance.]

7. What is the similarity between St. Elmo's fire andlightning? (Both are exchanges of staticelectricity.)

8. Why does lightning make a bright light and a loudboom and why is St. Elmo's fire a quiet glow?(The exchange of electrons in St. Elmo's fire isslow and steady instead of immediate.)

9. What is friction? (Friction is the resistance createdby two objects rubbing together.)


When you comb your hair on a dry, cold day. youprobably notice that your hair follows the comb or brush.

make a crackling sound.electricity by

rubbing one thing~ your hair with another the combAnother name for static electricity ssfricuon«!

etectrtcn». Can you tellYour hairs follow the comb for the same reason that

Greeks' amber drew or hits of Object> thathave different charges attract each other. Why do you thinkthen that each strand of hair pushes away or repels everyother strand of hair? Object> that have the same chargerepel each other.

46

57

Conclude the discussion. Tell your student that staticelectricity is produced by friction. Friction causes elec-trons to be exchanged. If the air is dry, it will not allowthe electrons to get back in balance. Thus, oppositelycharged objects will attract each other. When they meet,the electrons can get back in balance. Objects that havelike charges will repel each other. The electrons cannotget in balance between two objects that have the samecharge because both are unbalanced in the same way.

name _

Each row has two atom •. On the line below each atom, put. + to ,how It the atom h••• posl'lYecharge and a - to show IIthe elcm has a ne"ativi charge. On Ih.llne 10 the left of tee" ,aIr, t.1Iwhether the .toms will attract or repet •• ch oth.r.

Example: ® ®+-

@ @+ +

@ @

® ®-+

@ ®@ @

+

~19908obJonesUn'versltyf>ress Aeproduc1ionprohibiteCl

Lesson 12Evlh,llling t~ LeMon 14

auract

repel

repel

attract

repel

attract

D Sdence4NotebookPad<et

Evaluating the LessonDirect a not.ebook activity on page 14. Tell your stu-dent to follow the directions on the notebook page.

For Your InformationAnother grand display of electricity in the atmos-

phere is called Northern Lights or the aurora borealis.In the Southern Hemisphere it is called the aurora aus-tralis or Southern Lights.

These lights, usually greenish yellow, seem to hangdown from the sky like huge curtains. Sometimes thetop part of the "curtains" is dark red. Many times thereare several of these shining, curved sheets in the sky,one in front of the other.

The Auroras can also appear as a deep red glowcalled a veil. Although the curtain effect can usually beseen only near the North and South poles, the veil hasfilled skies over Mexico.

58 SCIENCE 4 HTE

FamilyTime 13

Looking AheadText, page 58


• An old orange, cantaloupe, or lemon.*• A large glass jar.

This Family Time may seem out oforder here, but you will need to beginthe following activity now in prepara-tion for Lesson 15.

InstructionsDirect your child's attention to the Finding Out ac-tivity on page 58. Ask him to read the page silentlybefore beginning this activity. Allow him to follow theinstructions in Steps 1 and 2.

First, the mold will appear white onthe fruit. When the mold is green, aspecies of Penicillium will be presentfor observation.


About FungiI. Get one old orange or cantaloupe. a magnifying glass.

and a large glass jar.

2. Let the fruit sit out all day. Then cover it with the jar.Leave it for several days until mold appears.

3. Remove the jar and observe the mold under amagnifying glass. Record your observations.

58

59

Lesson 13Electricity in

MotionText, pages 48-50Notebook, page 15

Objective

Prepare:• The copper wire by cutting it into two pieces: one

piece 1 foot long and the other 6 feet long. Then stripan inch of insulation from each end of both pieces ofwire.

• The galvanometer by wrapping the 6-foot length ofcopper wire around the compass about 5 times par-allel to the north and south markings, making surethat you can see the ends of the needle when it turns.Leave at least one foot of wire free at each end.

Preview


• Distinguish between a conductor and an insulator.


• Compass.*t• 1 dry-cell battery (1.5 volt). *• 7 feet of #20, #22, or #24 insulated copper wire. *t• 1 pair of wire cutters. *• 1 knife switch. *t• 1 glass or ceramic insulator from a telephone or elec-

trical wire (optional). *

Caution: When working with the dry-cell battery and the wire, do not leavethe wire connected to the battery whileunattended or for more than a few min-utes at a time. The wire will get hotand can bum; it can also create a firehazard if left alone. Leaving the wiresconnected for a longer time than nec-essary also causes the dry cell to loseits power quickly because there is noresistance in the flow of the current.

60 SCIENCE 4 HTE

Current ElectricityStatic comes from a word meaning "standing."

Although static electricity sorneume-, jumps Irom one placeto another, it does not keep moving. It is not very useful tous because it produces power only for a moment.

To he most useful, electricity must he moving. Anelectric current i...a !low 01 moving charges. Whenelectricity mov es, it can do work for us.

48


Direct a demonstration. Ask your student if he knowswhat a galvanometer does. Tell him he is going to con-duct an experiment to find out what a galvanometerdoes. Place the compass on a flat surface and positionit so that the needle points to the north and south sym-bols on the compass face. Loosen the nut on one of theterminals on the battery, wind one end of the wirearound the bolt, and tighten the nut. Touch the otherend of the wire to the other terminal for a couple ofseconds. The compass needle should swing abruptlyaway from its north-south position. (NOTE: See Figure13-1.) Ask your student if he knows why this happened.


To keep electricity acting, yOU must keep electrons outof balance with the protons. One way to do that is to usechemicals. Some chemical actions will make electrons movefrom one place to another.

Can you think of some things that use baueries? A cardocs. l'he battery of a car contains chemicals that acttogether to take electrons away from one place on thebattery called a terminal. Do you think that this terminal isa plus or it minus terminal? The batter} also has anotherterminal. What do you think. it i, called?

lhe extra electrons from the terminal Can travel if tht.'yhave ,ol11ething to travel along. Suppose a wire that allowselectrons to travel through it is hooked to the terminal.Where will the electrons go? They "ill go out through thewire. If the other end of the wire is hooked to the otherterminal. where will the electrons go?

The compass needle is magnetized andit follows the earth's magnetic field.The coil of wires creates a magneticfield when electricity flows through it.The magnetic field of the wire coil de-flects the magnetized needle. If theconnection between the two terminalswere broken, the electricity would notflow. The electrons would have no-where to go.

Figure 13-1

Galvanometer

49

61

-.~-- ptus terminal

Out-of-balance electrons tend to get back in balance. Atthe second terminal. the electrons again get into the groupsthey were in before the chemicals acted. But the chemicalsarc still active; the electrons are freed again; they go to theterminal. out through the wire. and to the other terminal.Can you see how a battery keeps electricity moving"

To have current electricity. you need two things. Youneed something that will keep electrons out of balance as abattery does. And you need a complete circle or path- acircuit.

Circuit comes from a Latin word meaning "to goaround." How is that name appropriate" What do youthink a circuit breaker does?

50

Figure 13-2

Galvanometer with switch

62

Leave the galvanometer assembled and connect oneend of the longer wire to a terminal on the dry cellbattery. Loosen both nuts on the knife switch. Makesure that the switch is open. Wrap the other end of thelong wire around one of the nuts on the switch andtighten it. Attach the short wire to the battery and theswitch in the same manner. (NOTE: See Figure 13-2.)Ask your student if he knows the purpose of the switchand what he thinks will happen.

Tell your student to watch the compass needle whileyou close the switch. Ask him if he can tell what ishappening. (You are now allowing the electricity to passall the way through the wire, somewhat similar to theway a drawbridge closes and allows cars to pass.) Askhim if he has seen something that serves the same pur-pose in his house. (His house has fuses and circuitbreakers.) Lift the switch to break the circuit. Whendoes this happen to a circuit breaker? (when the wire orcircuit gets too hot) Ask him why houses and otherbuildings would need something like a circuit breaker.(If the wires get too hot, they can cause a fire. Circuitbreakers and fuses open the circuit automatically sothat no more electricity can flow through.)

Ask your student whether electricity can flowthrough everything. (no) Explain that those things thatelectricity can flow through are called conductors, andthose that it cannot flow through are called insulators.Open the switch completely, moving the knife all theway back. Allow your student to place different objectsacross the metal clips of the switch to see whether theyare conductors or insulators. If the object is a conductor,the galvanometer will register a current; if it is an in-sulator, the galvanometer will show no movement.When your student has tried several different objects,ask him what kinds of things make good conductors andwhat things make good insulators. (Electricity will flowthrough most metals like gold, silver, copper, nickel,iron, steel, etc. It will not flow through many nonmetals,such as rubber, plastic, glass, paper, and wood.)

Teaching the LessonDirect a text activity on pages 48-50. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. When is electricity most useful to us?2. What makes batteries work?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. When is electricity most useful to us? (when it is

moving)2. Look at the picture on page 49. Why are the ter-

minals named plus and minus? (The plus terminalhas more protons than electrons, or a positivecharge; and the minus terminal has more electronsthan protons, or a negative charge.)

SCIENCE 4 HTE

3. In what direction does the electricity flow and whydoes it flow that way? (from the minus terminal tothe plus terminal; because the minus terminal hasmore electrons)

4. What makes batteries work? (chemical actions)How do these reactions produce electricity? (Yourstudent's answer will vary. The two terminals ofthe battery are made up of two different metals,usually copper (or carbon) and zinc. These twometals are separated by several chemicals; whenthese chemicals react, they remove electrons fromthe copper and take them to the zinc.)

5. What makes the battery run down? (The chemicalsare used up.)

6. What is a circuit breaker? (A circuit breaker issimilar to the knife switch [used in the galvanom-eter) or a drawbridge. Circuit breakers and fusesopen the circuit automatically so that no more elec-tricity can flow through.)

Conclude the discussion. Ask your student how insu-lators are useful if electricity cannot flow through them.(Answers will vary.) Tell him that insulators help keepelectricity under control. For example, most electricalwires are covered with an insulator so that the electricityis kept in the wires where it is safe. If one can be found,show him some sort of glass or ceramic insulator froma telephone or electrical wire. Explain that this insulatorkeeps the extremely powerful electricity in the wiresfrom corning down to the ground.

Evaluating the LessonDirect a notebook activity on page 15. Tell your stu-dent to follow the directions and complete the wordsearch.


name _

ClreI, HCh word In this puzzl,lh.t II r.lated 10 electriCity. You should find the following words wriHenforward, backward, dlagon.lly. up, or down.

batterychargecircuit

fusecurrentelectricityelectron

protonswitchgalvanometer

insulator

U B N A SUN I L G Y C U y

M A B H L L D C TOO N T C KV G I

M E

M S B QQ B

R I o 0

M T

w 0

T Z N 0 L J 0 W H L D P

BCURRS M J K M V

A M L v (G A L V A NOM E T E R)

H I l N Y G L Z D F Q AND Y

D Sdence4NoeobooII , •••••

LtuCln 13

EvalulUngthtL~ IS

For Your InformationSome batteries can be reused after they run down.

Examples of these are car batteries and nickel-cadmiumbatteries. The chemical solution or jelly (electrolyte) inthese batteries is not used up. Instead, electricity is pro-duced by a chemical reaction that coats the two metals(electrodes) with a compound of the electrolyte. Re-versing the current that flows through the cell returnsthe electrolyte to its original state. This recharges thebattery for another use.

63

Lesson 14Electricity andMagnetism

Text, pages 51-54Notebook, page 16

PreviewObjectives


• Describe how an electromagnet works.• Describe how a magnet can produce electricity.


• Home Teacher Packet, p. 9.• 16+ feet of #20, #22, or #24 insulated copper wire.*t• 1 iron bolt or rod, 4" to 6" long.*• Several paper clips.• 1 knife switch.*t• 1 pair of wire cutters.*• 1 dry cell battery (1.5 volt).*t• The galvanometer from Lesson 13.• 1 felt-tip pen (optional).• 1 bar magnet.*t• 1 toilet tissue tube.• 1 piece of cardboard.• Iron filings.*t

Prepare:• The wire by cutting it into two pieces: one piece 6feet long and the other 10+ feet long. After cuttingthe wires, strip about an inch of the insulation off theends of each wire with the wire cutter.

• The coil by wrapping the lO+-foot piece of wiretightly together around the toilet tissue tube. Removeit from the tube and connect it to the ends of the wiresextending from the galvanometer. (NOTE: See thediagram on the bottom of page 16 in the studentnotebook.)

NotesLeave the wires connected to the battery only long

enough to complete each experiment. Because the electriccurrent encounters no resistance, the dry cell will lose itspower rapidly.

64

About Electromagnets

1. Get one meter of insulated wire, a piece of iron rod,several small paper clips, a knife switch, and an energysource.

2. Following your teacher's instructions, wrap the wirearound the iron rod. Then attach the iron and the wireto the knife switch and the energy source.

3. Find out whether your electromagnet will lift a paperclip. Will it lift two? Record your observations.

54

If you have a dam in your area or haveaccess to a gas-powered generator,schedule a field trip for this lesson.


Direct a demonstration. Show your student the gal-vanometer. Allow him to hold the compass on a flatsurface so that the needle is standing still. Make surethat the coil is about one foot from the compass. Thenmove the bar magnet over or through the coiled wire.(NOTE: See the diagram on the bottom of the studentnotebook page 16.) As you do, the compass needleshould be deflected each time you move the magnetover the coils. If it is not, turn the magnet in the oppositedirection and try again. Tell your student that the magnetis producing an electric current as shown by thegalvanometer.Direct a Finding Out activity on page 54. Show yourstudent the iron rod and hold it over the paper clips sohe can see that the iron rod is not a magnet. Thenconnect the shorter wire to the battery and the knifeswitch by loosening the nut on one of the terminals on

SCIENCE 4 HTE

Another way to keep electricity moving is to use agenerator. A generator does not use chemicals. Why wouldit be better to find a way to make electricity withoutchemicals? Chemicals get old; they are used up; they arcexpensive.

Generate means "to make." But can a generator really"make" electricity? A generator actually gathers electricityand sends it where we can use it. Most generators changethe force of magnetism into electricity.

Magnets can create a force. If you put two bar magnetstogether north end to south end. the magnets will pulltogether. If you put them together at like ends, they willpush apart. The force that magnets make is closely relatedto electricity.

When a magnet is moved over metal, a current isprod uccd. When metal is moved over a magnet. a current isproduced. What has to happen for the current to beconstantly produced? Either the magnet or the metal has tokeep moving.

51

the battery, winding the exposed wire around the bolt,and tightening the nut. Do the same with the nut on theswitch. Attach one end of the longer wire to the otherterminal on the battery, following the same proceduregiven above, and wrap the wire around the rod ten times.Be sure to leave at least eight inches of both ends ofthe wire unwound. Then connect the wire to the otherside of the switch. (NOTE: See the diagram on the topof page 16 in the student notebook.)

Explain to your student that closing the switch al-lows an electric current to flow, producing a magneticfield. Close the switch and pick up first one paper clipwith the rod, and then another. Ask him to guess thenumber of paper clips the rod can pick up. Put the paperclips in a pile and hold the rod directly above them.Allow him to count the number of paper clips that therod has picked up. Ask him what he thinks will happenby wrapping more of the wire around the rod or byadding more batteries. (The strength of the electromag-net can be increased.) Allow your student to try wrap-ping more of the wire around the rod. Allow him topredict how many paper clips the magnet will pick upas you vary the number of coils or batteries. Use thechart of the electromagnets from page 9 of the HomeTeacher Packet. Let your student choose objects to pickup and vary the number of coils. As he makes his ob-servations, let him record the data on the chart with afelt-tip pen.


You can produce a current by moving a magnet over ametal wire that is part of a circuit. Do you think you couldsend enough electricity along a \\ ire this way to light anelectric bulb? Do you think. if you could, that you wouldbe able to keep it lit long" You would probably soon decidethat you would rather sit in the dark than try to keep theelectricity coming.

In 1831 a man named Michael Faraday had come toabout the same conclusion. He had tried a dozen ways toincrease the power of his magnet and wire current-maker.He even carried a magnet and wire around in his pocket tohelp him think about the problem. Onc day, as he workedin his laboratory. he happened to wrap a wire around a ringseveral times. Hc looked at the coil in his hand. andsuddenly, after months of pondering, he had an idea.

Faraday made another coil of wire and hooked the wireends to a meter that registered electrical current. When hepassed a magnet in and out of the coil. a solenoid, thcneedle on the meter shot over to the right. He hadgenerated electricity!

52

Direct an observing activity. Place the bar magnetunder the cardboard. Sprinkle the iron filings onto thecardboard and tap it until the filings follow the magneticlines of force. Ask your student what he thinks createsthe pattern. (The pattern that the filings form indicateswhere the magnetic force is.) Next, place the rod underthe cardboard. Ask him what he thinks will happen.Close the switch and tap the cardboard. Show yourstudent that the lines of force are similar to that of thebar magnet.

Teaching the LessonDirect a text activity on pages 51-53. Use the follow-ing questions to arouse your student's interest in whathe is going to read.1. How does a generator work?2. What is a turbine?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Where does the electricity come from that you use

in your home? (generators)2. How does the galvanometer that you used in your

lesson today work? (The electric current goingthrough the coiled wire creates a strong magneticfield that deflects the compass needle.)

65

coils of wire

~-,,- ...-~- -------- ----~~--

electromagnet

Today great amounts of electricity come fr0111 hugegenerators that work on the same basis. Giant coils.electromagnets callcdJieltl coils, produce thousands oftimes as much current a~ Faraday's first small experiment.Water is often used to Iurn the coils.

Big dams provide the water power for such generator"The water pours into the dam. The energy of the rushingwater turns a water whee! called a turbine. lhc turbinecauses the coils to turn; the turning coils produce anelectrical current; the electricity travels out of thegenerators and is sent out to hundreds of houses andindustries.

If you were lo go on a lour to a big dam. an elevatorwould whisk you down into the middle of the dam. Youwould be about fifty stories below t he tor of the dam whenyou stepped out of the elevator. Then you would walk intothe powerhouse, a huge room with long windows that lookout over the river. 1n this room are the generators, whichmake only a quiet hum. Hut these generators are puttingout more energy than fifty thousand wild horses.

Mr. Faraday would certainly be surprised to see theuses his invention has been put to. If he could visit yourclassroom. what would you show him first?

53

3. Michael Faraday found that moving a magnetalong an electric wire produces electricity. Whatproblem did he have with this method? (Theamount of electricity produced was very small.)

4. How could the amount of electricity produced beincreased? (Wrap the wire in coils.' this increasesthe amount of wire that is affected by the magnet.)

5. What is a turbine? (a water wheel that causes thecoils to turn)

If your child has ever been to a damor has ever seen a small gas-poweredgenerator, you will want to refer to itas you discuss generators.

Conclude the discussion. Direct your student's atten-tion to the picture on page 53. Ask him how the gen-erator operates. (Coils spin around magnets and pro-duce electricity.) Ask him how electricity and magnet-ism work together in things around the house. (themotor in the hair dryer,' the telephone,' the stereosystem)

66

name _

Draw the direction 01 the lIow 01 current and then draw the magnetIc: lIeld.

rr)

Show the reaction of the compass.

~1990BobJoo •• Unlv'r.llyPr' ••. R'produetionprot\lblled.

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Lenon 14

Evalu.tlngUltL."OlI

Evaluating the LessonDirect a notebook activity on page 16. Tell your stu-dent to follow the directions on the notebook page. Heshould try to show the magnetic field with the mostdetail possible.

SCIENCE 4 HTE

16

For Your InformationMichael Faraday (1791-1867) was one of the great-

est scientists in history. Because his family was poor,he started out with little formal education. When hebecame an apprentice to a bookbinder, he read all thescience books that came to the shop. One day a customergave Faraday some tickets to science lectures by SirHumphrey Davy, the leading scientist of the times.

Davy was impressed with the enthusiasm and talentof the boy and hired him as a laboratory assistant. Even-tually Faraday surpassed his teacher, devising theoriesand conducting experiments in electricity and magnet-ism. Some of his work led to the electric power industryof today; some of it laid the foundation for Einstein'swork with the theory of relativity.

Faraday was a sincere Christian. A reporter onceasked him about his speculations on the hereafter."Speculations," he asked with astonishment. "1 havenone. 1am resting on certainties. 'I know whom 1havebelieved, and am persuaded that he is able to keep thatwhich I have committed unto him against that day' "(II Timothy 1:12b).

He rested on certainties in his work too. He believedthat science was merely man's investigation of God'screation, and he rejected theories that did not align withthe truth. Respected by the scientific community, hegave popular weekly lectures on his work. At Christmashis talks for children made him a favorite speakeramong the young as well. Faraday's life shows that truescience and Biblical faith are in harmony.


CHAPTER

4Plants

~

Lessons 15-19

~Plants

55

68

This chapter introduces ways of classifying plants:plants with or without tubes, plants with or without seeds,and flowering plants that are divided into monocotyledonand dicotyledon subclasses. Each lesson includes a hands-on activity to aid your student in understanding the differ-ent plant groups.



* Samples of blue cheese and Camembert cheese (op-tional) (Lesson 15)

* 1 magnifying glass] (Lessons 15, 18, and 19)* Pond water or water from a fish tank with visible

algae (Lesson 16)* 1 microscopet (Lesson 16)* 1 microscope slide+ (Lesson 16)* 1 microscope cover slip+ (Lesson 16)* 1 medicine dropper (Lesson 16)* Several spruce needles (Lesson 18)* 2 wildflowers or cut flowers (Lesson 19)

SCIENCE 4 HTE

Lesson 15FungiText, pages 56-59


~ P__re_v_i_e_w ~1 1~ L_e_s_so_n ~Objectives

Given proper instruction, the students will be able todo the following:

• Identify types of fungi.• Observe the hyphae of mold with a magnifying glass.

Introducing the LessonDirect a Finding Out activity on page 58. Allow yourstudent to observe the moldy orange or other moldyfruit by using a magnifying glass. To direct his obser-vations, ask questions such as the following. (NOTE:Your student will record his observations during theEvaluating the Lesson time.)

1. What color is it?2. Is it soft or hard? Does it spring back when you

touch it?3. What happens when you blow on it?4. What do you see under the magnifying glass?5. Do you know what has grown on the fruit? (mold)

Materials ------Have available:

• The moldy orange, cantaloupe, or lemon from FamilyTime 13.

• 1 magnifying glass. *t• 1 large straight pin (optional).• Samples of blue cheese and Camembert cheese

(optional). *• Home Teacher Packet, p. 10.

It would be beneficial for your child tohave several pieces of moldy food,such as bread, fruit, or meat, availablefor observation.

Chapter 4: Introduction 69

.,Build ye houses, and dwell in them; and plant gardens,and eat the fruit of them. " lereniiati 29:5

God created many different plants. How are plants

alike, and how are they different? How can you tell oneplant from another plant" To decide, you need to lookclosely at the parts of a plant. For example. are thereleaves? What shape are the leaves? What size" Are thereflowers? What color are the flowers? How big are theflowers'? Are the stems soft or woody?

Answering questions like these will help you to classifyor "group" plants. Can you think of somc things that areput into groups by how they are alike? How about books inlibraries" /\11 the history books are together, and all thescience books arc together. Why do we make groups ofthings like books?

Scientists classify plants to help identify them. Scientistswho study plants are called botanists. Botanists look at thepans of plants and observe how plants arc alike ordifferent. Plants arc classified into two large groups: thosewith tubes and those without tubes.

Do you remember what tubes carry? They carry foodand water inside the leaves. stems. and roots. You can seesuch tubes if you break a stalk of celery in half.

56

Teaching the LessonDirect a text activity on pages 56-57 and 59. Use thefollowing questions to initiate your student's interest inwhat he is going to read.

1. What is classifying?2. Where does a fungus get its food?3. What are spores?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.

1. What is the importance of classifying things?(Classifying organizes things by similar character-istics, makes them easier tofind, and aids infindinginformation about other similar things.)

The present scientific system of clas-sification was proposed by CarolusLinnaeus [li-ne' as] in the 1700s. Hedivided living things into seven basiclevels. They are arranged from thelargest to the smallest: kingdom, phy-lum, class, order, family, genus, andspecies. It will not be necessary foryour child to know these terms. Youmay wish to write them on the WriteIt flip chart for his information.

70

Plants with No TubesPlants with no tubes usually grow close to water or in

damp, shadvplaces. Why do you think they grow there?

Fungi are not green because they have 110 chlorophyll.Docs a plant need chlorophyll to make food? How can aplant live \\ ithout chlorophyll? Because fungi do not maketheir food. they do not need Chlorophyll. II they do notmake food. how do you suppose they get food" Fungi gettheir food from other organisms that may be dead or alive.Have you seen these fungi? Where arc they getting theirfood?

57

2. How will you classify plants during this chapter?(those with tubes and those without tubes)

3. Look at the picture on page 57. What is growingon these surfaces? (mold)

4. Where does a fungus get its food, since it does nothave chlorophyll? (from rotting logs, living plants,or other media that can provide nutrients)

5. Often fungi are thought of in an unpleasant way,but many good things come from fungi. Can youthink of any? (Your student's answers will vary.The antibiotic penicillin comes from a mold grownon citrus fruits. The strong, sharp taste of bluecheese and the mild, creamy taste of Camembertcheese are results of molds.)

You may want to have samples ofthese cheeses available for your childto taste. Most children will not care forthe taste of blue cheese but may enjoythe Camembert.

6. Where do molds grow? (Molds can grow on mostfoods, but they also grow on paper, leather, andwood. Generally they grow best in warm, moistplaces, but they have been discovered growing attemperatures near freezing.)

SCIENCE 4 HTE

These fungi arc called mold,', They grow on fruit, bread,and even bathtubs and showers, Another fungus is themushroom, Mushrooms grow on soil and on living or deadtrees, Have you seen these mushrooms?

Fungi produce other fungi by microscopic roundstructures called spores, The fungi produce so many sporesthat at times appear to be a cloud of smoke coming fromthe fungus,

People eat some kinds of mushrooms, You can buythem in grocery stores, Never eat a mushroom you findgrowing in your yard or in the woods, It may be apoisonous kindl

plant world

tubes no tubes

fungi

59

7. In what ways are molds beneficial? (Answers willvary, Molds can be beneficial in flavoring foods,providing cortisone [a pain reliever J, andantibiotics ,)

8. What do you normally do with food when mold ispresent? (throw it away) However, once the moldlayer has been removed, most foods are still edible.For example, cheddar cheese will often have awhite mold growing on it. If this mold is cut offwith a knife, the cheese underneath is still good toeat.

Display page 10 of the Home TeacherPacket for the following discussion.As you discuss the different stages ofgrowth, allow your child to find thecorresponding picture on the visual.

Conclude the discussion. Ask your student what fungihave instead of seeds. (spores) Spores are very tiny,often smaller than dust. Can you find the spores on thevisual? As the spore lodges into its growing place, tinyhairlike threads begin to form, These are called hyphae[hi'fe]. In some fungi, these hyphae form a tangled webwhich is called mycelium [ml-se'Ie-orn]. Once the my-celium has grown sufficiently, it begins to form the


fruiting body, As the fruiting body breaks through thesurface, it is called the button stage. As it grows, themature fruiting body is formed, which can then repeatthe process of releasing spores and making new plants.Some fungi can produce more than a half mile of hyphaewithin twenty-four hours. These tiny threads providethe food and water necessary for the fungi. Ask yourstudent to name a fruiting body that people eat.(mushrooms)

71

name _Cui oul Ih. 'QU"" 01Ih. tII. oyol. 01• mu,hroom, GI.elhem In00"",' order onlo nQlellook_ 11,

I4

• ,990 Bob Jones University Pres •. Reproduction prohibited.

D Sdence4Notebook Pwet

Leaton 15

Ev,lu,tlnllltJ.lnlOtl

Evaluating the LessonDirect the use of notebook pages 17-18. Tell yourstudent to cut out the squares representing the life cycleof a fungus. Tell him to glue the squares in correct orderon notebook page 18,

72

17

,- na_m_e-=~--------~============~

!

Draw your observation 01 the moldy orang •.

\

/

18D SCience 4Notebook Packet

.'990 Bob Jones University PrH •. Reproduclion prohibited

SCIENCE 4 HTE

About FungiI. Get one old orange or cantaloupe. a magnifying glass,and a large glass jar.

2. Let the fruit sit out all day. Then cover it with the jar.Leave it for several days until mold appears.

3. Remove the jar and observe the mold under amagnifying glass. Record your observations.

58

Complete the Finding Out activity on page 58. In-struct your student to draw on the bottom half of note-book page 18 the hyphae on the moldy orange that heobserved earlier.

To extend this experiment, encourageyour child to take a fresh orange andthen to transfer mold from the moldyorange into the fresh orange. This canbe done by scraping mold onto a largestraight pin and then injecting it intothe fresh orange. Allow him to observeit daily. Tell him to notice any changesin the orange, especially near the pointof injection. See how long it takes forthis orange to become moldy:


For Your InformationLichens [li'kenz] are often grouped with fungi. Li-

chens are "dual organisms" composed of a fungus andan alga. When two things live together for mutual ben-efit, they are said to have a symbiotic relationship.

The fungus supplies the moisture, minerals, and pro-tection for the alga. The alga, which carries on photo-synthesis, provides food for the fungus. This symbioticrelationship fascinates botanists and is one of the manymysteries still to be solved.

Lichens grow just about anywhere the air is clean:on rocks, trunks of trees, logs, sand, and bare soil. Li-chens are often used as environmental monitors. Thedisappearance of lichens from an area gives warning ofair pollution. Lichens grow slowly, thriving on the sunand growing in climates and areas where other plantscannot grow. They can grow in moist, cool climates likethe mountains and forests or in hot, arid climates likethe desert. Some lichens have even been discoveredgrowing near the North and South poles.

Lichens are useful in many ways. Reindeer and car-ibou eat certain lichens. The best known use has beenthe production of dyes from lichens for clothing andlitmus paper, which is used to test the acidity of solu-tions. At least half of the species have antibiotic prop-erties. This special quality is due to a rich assortmentof chemical compounds that only lichens can produce.

Finally, lichens are well known for their ability toenrich the soil and make new soil. Lichens growing onrocks give off carbon dioxide gas which combines withwater to form carbonic acid. This acid causes the rockto become soft and crumbly, which eventually changesthe rock into soil. As lichens decompose, the existingsoil is enriched by the nitrogen they contain.

73

Lesson 16Algae, Mosses,and Liverworts


PreviewObjectives ------


• Differentiate between algae, mosses, and liverworts.• Identify algae under a microscope.


• Home Teacher Packet, p. 11.• Pond water or water from a fish tank with visiblealgae.*

• 1microscope.*t• 1 microscope slide.*t• 1 microscope cover slip.*t• 1 medicine dropper.t• 1 toothpick.

name _

0,.. • picture 01 wn.t the .ISI" looked like under the microscope. Color the picture.

.,m Sob Jonu University Pr811. Aeproductlnn prohlblt.<I.

O Sdence4-,- Leaton 16

Ev.lu.t!ng I~ ltMOn 19


Display the microscope from page 11of the Home Teacher Packet. You maywant to spend a few minutes instruct-ing your child about the care of a mi-croscope before beginning this lesson.

Direct an investigation. Allow your student to preparethe microscope slide by placing a drop of water on theslide with the medicine dropper. Using the toothpick,mix some algae into the drop of water. Place a coverslip over the drop of water on the microscope slide.(NOTE: See Figure 16-1.)

Place the prepared slide of algae under the micro-scope. Allow your student an opportunity to observe the

74

algae under the microscope. Tell him to sketch on page19 of his notebook the algae as it appeared under themicroscope. Instruct him to add details and color to hissketch and to add his picture to his notebook.

Figure 16-1

SCIENCE 4 HTE

AlgaeA second group of tubeless plants are the algae. Algae

comes from a Latin word meaning "seaweed."Algae arc small or large. Some can be seen only through

a microscope. Others may be as long as a football field.Algae are grouped by color. They may be green, bluishgreen. brown, or red. They all have chlorophyll. Do theymake their own food?

Algae grow in ponds. streams, lakes, or oceans. Thebrown and red algae usually grow in the ocean. Most of thegreen and bluish green algae grow in ponds and streams.

Algae may also live on land. For example, some growon brick walks. and others grow on tree trunks. Most ofthese are green algae.

Many animals eat algae for food. and people use algaeto make many products. For example, a material frombrown algae is used in ice cream and whipped-creamproducts.

60

Teaching the LessonDirect a text activity on pages 60 and 61. Use thefollowing questions to initiate your student's interest inwhat he is going to read.

1. What do all algae have in common?2. What color are algae?3. Would liverworts grow in the desert?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Although algae are different colors, what do all

algae have in common? (chlorophyll)2. What process do algae go through that allows them

to make their own food? (photosynthesis)3. What product do green plants release when they

make their own food? (oxygen)


Mosses and LiverwortsThese small green plants grow in damp. shady places

on rocks, on trees, and in soil. A few grow in the water.Mosses and liverworts grow from spores. What other

tubeless plant grows from spores'? Special structures format the top of plants which hold the spores. They are calledcapsules. When the capsule bursts open. the spores escapeand are carried by the wind to new place; to grow.

Mosses and liverworts grow in many places- fromtropical jungles to arctic rocks. Sometimes the mosses andliverworts grow so close together that a soft, green carpetor cushion is formed over rocks and soil.

61

If you live near a pond, you may wishto observe the algae floating during theday. When your return at night, thealgae will be gone. During the day,photosynthesis occurs, producing bub-bles of oxygen. These oxygen bubblesare trapped in the stringy, hairlikestrands of the algae, causing the algaeto float. When night comes, photosyn-thesis ceases and no oxygen bubblesare produced. The bubbles still trappedin the algae dissolve, and the algaeusually sink.

4. What is another name by which algae are oftencalled? (seaweed) It could also be called rockweed,soil weed, iceweed, animal weed, or plantweed.

5. Where can algae be found growing? (water andland)

6. What colors of algae are mentioned in the text-book? (green, bluish green, brown, and red)

7. Mosses and liverworts are often confused with al-gae. How could this confusion happen? (They looksimilar. They grow in the same locations. The ma-jority of them grow best under moist conditions.)

75

8. Name at least one thing that the mosses, liverworts,and algae have in common. (They all grow fromspores.)

9. One moss that is useful to man is peat moss. Haveyou ever seen it or used it? (Answers will vary.)Dried peat moss ean be used as a packing materialfor glassware and plants. Have you ever seen peatmoss used in a garden? (Answers will vary.) Gar-deners use peat moss as a soil enricher. Peat mossloosens hard packed soil such as clay and helps tohold moisture in the soil.

10. Would liverworts grow in the desert? (No, theygrow in moist environments, even in the Antarctic.)

Evaluating the LessonSearch for algae. Allow your student to look for fooditems at home that contain some kind of alginate. Re-mind him of the foods mentioned in the lesson. (icecream, puddings, pie fillings, salad dressings, and syr-ups) One of the most common ingredients listed on foodlabels is sodium alginate. It is generally found in pud-dings and pie fillings. Remind him to check more thanone brand of product. Some medicines also have a typeof alginate called alginic acid. You may wish to contin-ue this activity the next time you go to the grocery store.

For Your InformationLiverworts may have received theirname from the ancient belief that theycould cure liver diseases and other dis-orders. However, there is no scientificbasis for this claim.

Harmful red tides are also the result of algae. Thesedreaded red tides are found along the coasts of Maine,Massachusetts, New Hampshire, California, Florida,Texas, Peru, Japan, Australia, India, and parts of Africaand Europe.

Red tides are caused by tiny plants called dinoflag-ellates. Some scientists group them with the algae be-cause they carryon photosynthesis. Usually the red tidescome in late summer or early fall. Scientists have notyet discovered why they occur.

Red tides are harmful to man because shellfish suchas clams, mussels, scallops, and oysters eat these plank-ton, which are poisonous to man. (NOTE: Plankton aremicroscopic plant and animal organisms that float ordrift in large numbers in fresh or salt water.) Theseplankton do not affect the shellfish that eat them, butpeople who eat the shellfish become extremely ill. Ared tide also affects the fishermen financially, becausethey cannot work during that time.

Conclude the discussion. Explain to your student thatone of the most useful algae is from the group calledbrown algae. The brown algae often attach themselvesto rocks or ocean bottoms and are commonly calledseaweed or kelp. In the underwater forests, hundreds ofkelp plants grow together to form kelp beds. These kelpbeds are beneficial to many sea creatures. Fish of dif-ferent sizes and shapes make the kelp bed their home.Ask your student to name sea creatures that might livein a kelp bed. (shrimp, lobster, and sea urchins) Thekelp bed provides food for these creatures and offersprotection from predators. (Bible Promise: I. God asMaster)

Kelp beds have also been used by man. Ancientsailors used kelp beds as navigational tools. People inGreat Britian harvested kelp as fertilizer and for use inglassmaking. Today, kelp is still harvested for food inJapan. Ask your student if he would like to try to eatsome seaweed. Why or why not? (Answers will vary.)You may use this opportunity to talk about attitudestoward foods.

Another product widely used is algin. It is found inthe cell walls of kelp plants. It allows kelp plants tobend and stretch and makes the surface of the plantslippery. This is the product that is used in ice cream,puddings, pie fillings, salad dressings, and syrups. Alginis generally listed as an ingredient called alginate.

76 SCIENCE 4 HTE

Lesson 17FernsText, pages 62-64Notebook, page 20

Preview LessonObjectives

You may want to give your child theexperience of seeing different ferns bytaking him to a plant nursery eitherbefore or after this lesson.

Introducing the LessonIntroduce the song. Guide your student in hummingthe familiar tune to "My Bonnie Lies over the Ocean."Sing the "Fiddlehead Song." Display the words to thesong on page 12 of the Home Teacher Packet. Tell yourstudent that he will sing these new words to the tune of"My Bonnie Lies over the Ocean." This song willintroduce what your student will be discussing. Guidehim in singing all the verses to the "Fiddlehead Song."Conclude the song. Ask your student what happenedto the boy after he ate the fiddleheads. (He died.) Askhim to find the reason in the song that he died. (Hepicked the wrong kind offiddleheads.) Tell your studentthat some kinds of plants are edible, but others are not.Remind him of his lesson on fungi. As he learned inthat lesson, some mushrooms can be eaten; others thatoften look like the edible mushrooms are poisonous.Tell your student that only an expert should preparewild plants to be eaten.


• Classify terms associated with plants into major plantdivisions.

• Recognize that not all ferns are edible.


• Home Teacher Packet, p. 12.


Plants with TubesMost of the plants God created have tubes. These plants

all have roots. stems, and leaves. They are said to be "true"plants because they have tubes in them. Some of the mossesand liverworts have structures which look like roots, stems,and leaves. But remember, mosses and liverworts have notubes.

62

Teaching the LessonDirect a text activity for page 62-64. Use the followingquestions to initiate your student's interest in what heis going to read,1, Into what two smaller groups have botanists clas-

sified plants with tubes?2, What are fiddleheads?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read,1, Since there are so many kinds of plants with tubes,

into what two smaller groups have botanists clas-sified them? (those that produce seeds and thosethat do not)

2, Look at the picture of the fern on page 63, Theword/ern actually means lacy or feathery, Do youthink this is an accurate description of a fern? (yes)

3, Where do ferns grow? (where there are mild tem-peratures and moisture) (NOTE: Ferns that growinside often need to be misted daily with a finespray of water to increase the humidity.)

4, What are the curled-up fronds called? (fiddleheads)5, What do people in northeastern United States do

with fiddleheads? (eat them)

78

Since there are so many kinds of plants wit h tuhes,botanists have classified the tubed plants into two smallergroups: those that produce seeds and those that do not.

plant world

Plants with No SeedsA group of tubed plants that do not produce seeds arc

the ferns. God created many different and beautiful ferns.Most ferns have large. split leaves called fronds. Look atthe fronds on these ferns. Have you seen any of thembefore?

New fronds are all curled up, and as they grow theyuncurl. The curled-up fronds are calledfiddlefJead,. Canyou guess why? In the northeastern United States peoplecat fiddleheads. You can buy them there in some grocerystores.

63

You may want to relate the followinginteresting information to your child.In northern New England and NewBrunswick, Canada, fiddleheads arecultivated as a vegetable. Fiddleheadsare canned, frozen, or sold fresh inmany grocery stores. However, thetype of fiddleheads that are gathered toeat are from the fern called the OstrichFern (Matteuccia). Fiddleheads taste alittle like asparagus when simmered inboiling water. They are used fresh insalads, folded into omelets, or used incasseroles as a substitute for aspara-gus. Other recipes for fiddleheads ex-plain how to use them in soups, frythem in oil, and even make ice creamfrom them!

6. Look at the picture on page 64. What are thesebrown spots? (spore containers or sori)

Conclude the discussion. Tell your student that formany years scientists could barely see the spores offerns with a microscope. Fern spores are smaller thaneven a speck of dust. Now a more complicated micro-scope called a scanning electron microscope allows sci-entists to know more about the structure and develop-

SCIENCE 4 HTE

Ferns produce new ferns by spores. The spores areproduced on the underside of their leaves. Have you everseen rows of small brown lumps on ferns') Those lumps arenot bugs hut spore containers.

The small brown lumps will burst open. and the tinyspores will fall to the ground. or they will be carried awayby the wind. If a spore lands where it is warm, moist. andshaded. the spore will become a new fern.

You can find ferns in many places in the world. Theyarc most abundant in forests and in the tropics. Do youhave an~ ferns growing around your house?

64

ment of spores. Scientists have found crests, ridges, andwartlike or spinelike structures on many fern spores.

Evaluating the LessonDirect a notebook activity on page 20. Instruct yourstudent to unscramble the words at the top of the page.These words have been used in prior lessons. After heunscrambles the words, direct him to write the wordsunder the correct column on the notebook page.

For Your InformationThe life cycle of ferns has two stages. The first stage

is called the sporophyte generation. During this stage,sporangia develop inside the sori. The sari are the smallbrown spots located on the underside of the fronds.When the sporangia burst, thousands of spores are re-leased into the wind.


name _

Un.cremble the following word. and then pl.ce them under the correct heading. Some words may beplaced under more than one he.dlng.

hidaddflee nilag

20

odml

pkel rosspe momshorus

dronfs bedtu cepinillmui

garapasus eewsaed weldmis

Fungi Alga. Ferns

mold algin fiddlehead

spores kelp spores

mushrooms spores fronds

penicillium seaweed tubed

mildews asparagus

°llKIOBobJOII'.Unlvef.UyPr •••. R.p.oductionprohlblted.

'0' . ScIence 4~Padlet

teeecn 11

EVllulUngtneleuon

79

FamilyTime 18Nature Walk

MaterialsDirect a nature walk. Give your child a list of itemshe should try to find on the nature walk. (NOTE: Belowis a sample of the list that you may use. Other itemsmay be substituted on the list depending on the area inwhich you live.) Give your child page 13 of the HomeTeacher Packet to use as a guide for collecting. Providea small disposable shopping bag to collect his speci-mens. Explain that he should look for as many differentobjects as possible. A suggested list of items follows:

• browned pine needles fallen to the ground• pine branch with cones still attached• piece of pine wood showing growth rings• open pine cone• closed pine cone• needlelike leaves in a cluster• flattened needles• spruce needles• juniper needles• spruce cones• cedar cones• larch cones

Have available:• 1 shopping bag.• Home Teacher Packet, p. 13.

80

In this Family Time you will be takinga nature walk to look for coniferousbranches and cones. A park would bean excellent place for your walk.

You may wish to use the nature walkas a treasure hunt and divide your fam-ily into groups. Each group would re-ceive points only for different objects,not for the total number of objects. Al-low an allotted amount of time to findthe items on the list. Compare the listwith the items in each bag. Give pointsfor each item collected. Announce thewinner.

SCIENCE 4 HTE

Lesson 18Conifers


PreviewObjectives Materials


• Identify types of conifers by their leaves and cones.• Illustrate a spruce needle cross section.

Have available:• Home Teacher Packet, p. 14.• A Write It flip chart.• Scissors.• 1 magnifying glass. *t• Several spruce needles. *


About ConifersL Get some spruce needles, a small pair or scissors, and a

magnifying glass,

2, Cut a needle hall' crossways,

3, Look at cutglass, Can you see

4, You arc looking a cross seaton of spruce needle,

5, Record how the cross

68


Direct a Finding Out activity on text page 68 andnotebook page 21. Instruct your student to follow theinstructions on page 68, using the spruce needle. Tellhim to draw an enlarged picture of the cross section ofthe spruce needle on the top of notebook page 21.

The bottom of notebook page 21 willbe used during Evaluating the Lesson.

82

Draw the spruce needle ercee-eeeucn In the magnifying gl •••.

name _

Match then cones 10 their corresponding tr•••.


Cl990BobJone5Unj~er5ityPr~_Reproduc1ionp'ohibi1ed

Lesson 18Evalu;!Iting the Leeson 21

SCIENCE 4 HTE

Plants with SeedsMost plants with tunes produce seeds, Botanists cia>sify

the seed plant« into tw 0 groups: those that produce seeds inflowers and fruits and those that produce seeds in cones,Conifers

Conifers arc cone-producing trees. Have you ever seenany of these conifers'}

Conifer leaves have two basic shapes, Can you tell vvhutthose two shapes are by looking at these pictures'?

plant world

tubes no tubes

seeds no seedsI

flowers cones fernsand fruits

65

Teaching the LessonDirect a text activity on pages 65-67 and 69. Use thefollowing questions to initiate your student's interest inwhat he is going to read.

1. Into what two groups do botanists classify seedplants?

2. What are trees that do not lose their leaves in thefall called?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Into what two groups do botanists classify seed

plants? (those that produce seeds in flowers andfruits and those that produce seeds in cones)

2. The word conifer actually means' 'cone-bearing."Name some uses you have seen for pine cones.(wreaths, decorations, starting fires, crafts)

For the next question, display the pinecones on page 14 of the Home TeacherPacket.

3. Look at the pine cones on this visual. Many yearsago on country farms, pine cones were used as


juniper

Conifers are sometimes grouped by their leaf shapes andsizes. Pines and larches. for example. have needlelike leavesin clusters.

Firs and hemlocks, on thc other hand. have flattenedneedles. Hemlock needles are shorter than the fir needles,

Spruce needles have four sides. How can you tell aspruce needle from a hemlock needle?

66

weather indicators. Can you think of a way thatpine cones could be used as weather indicators?(Your student's answer will vary. The scales of thecones open in dry weather, but when it is damp,the scales close up to keep the seeds dry. By ob-serving the scales, farmers could predict whenrainfall would occur.)

4. Look at the two pictures on the top of page 66.How are these leaves shaped? (needlelike in acluster)

There are many varieties of pine trees,but the leaves of the pine trees are gen-erally long and grow in clusters of two,three, or five. Each needle has a thick,waxy covering that helps reduce theloss of water. Because of this covering,pine trees can grow in drier climatesthan other conifers.

S. What kind of a pattern do larch needles grow in?(circular cluster) Larch trees grow in the coldestclimates.

6. Look at the picture of the fir and hemlock. Whattype of leaves do these trees have? (fiauenedneedles)

83

Cedars, redwoods, and sequoias all have scalelikeleaves, Look at the photograph" Try to name the coniferspictured below,

Because most conifers do not lose their lcave-, in the fall.they are said to he ~\'erKreel1,A larch and a dawn redwoodwililosc their leaves every !'aIL Tree, that lose their leavesare deciduous.

67

7. Compare the pictures of the spruce needles and thehemlock needles. Christmas trees are often sprucetrees.

8. Look at the pictures on page 67. What type ofleaves do these trees have? (scalelike leaves)

9. What are conifers that do not lose their leavesevery fall? (evergreen)

10. Look at the picture of the cones on page 69. Whatdo you think the purpose of the cone is? (The conesare protection for the seeds that are inside.) Pineseeds develop in pairs and have a thin, delicatewing. What purpose would the wing serve? (It al-lows the wind to carry the seed.)

Conclude the discussion. Cones grow in many shapesand sizes. As you discuss the following cones, write thename of each and a brief description on the Write It flipchart. (NOTE: See the information below.) Tell yourstudent that other conifers, like the cypress, have small,round cones that often grow in clusters. When the conesare young, they are blue green and tightly closed. Asthey mature, they turn brown and open their scales. Truecedar cones are egg-shaped and smooth. They growupright on the branches of the tree. They also take upto three years to mature. When they mature, the tipbreaks; the seeds, which are still attached to the scales,fall to the ground. Ask your student which conifer hasberrylike cones. (junipers)

84

fII/II! •••. -.•, .Conifer cone, grow in many different shapes and sizes.

Look at the picture. Have you ever seen any of these cones'!Where have you seen them"

How would you describe each of these cones? Are theylong and narrow" Big and fat" Short and narrow? Spiny'How are they different trom each other'?

Some conifers do not haw cones like most of the otherconifers. Their cones arc berrylike. Junipers have this typeof cone. The oil from juniper berries j'l used in makingperfumes and medicines,

Because conifer wood is soft, we can make manyproducts from it. Paper comes lrorn the wood of conifers,and so does lumber for house>, Whole trunk> of someconifers become telephone poles and boat docks. Can youthink of any other things made from woods like pine andcedar?

69

Information for the flip chart:• cypress-small, round cones• cedar-egg-shaped and smooth• juniper-berrylike

Evaluating the LessonDirect a notebook activity. Instruct your student tomatch the cones to the correct conifer name at the bot-tom of the notebook page. Display the Write It flip chartwith the information about cones.

SCIENCE 4 HTE

For Your InformationThe conifers are classified into four basic families.

The pine family (Pinaceae) is most easily recognized.The eastern white pine was one of the most importanttimber trees in North America. Its wood was used forships' masts, houses, flooring, and other uses. Becauseof the exploitation of these great forests nearly a centuryago, they are carefully conserved today. Larches, hem-locks, cedars, and balsam firs are also classified underthe pine family.

The yew family (Taxaceae) includes both shrubsand trees. The wood from the English Yew, a nativetree of Europe and Asia, was once used to make bowsfor English archers.

The redwood family (Taxodiaceae) contains the gi-ant sequoias, the huge redwoods of California, and thebald cypress. A new member of this family, called thedawn redwood, was found in 1946 in central China.

The cypress family (Cupressaceae) all have small,scalelike leaves. This family includes junipers, cypress,and arborvitaes.


Lesson 19FloweringPlantsText, pages 70-76Notebook, page 22

PreviewObjectives


• Differentiate between monocotyledons and dicot-yledons.

• Identify parts of a flower.


• Home Teacher Packet, p. 15.• 2 light-colored felt-tip pens (optional).• 2 wildflowers or cut flowers.*• 1 magnifying glass.*t

NotesYour student will be classifying the flowers into the

two classes, monocotyledons and dicotyledons. Somemonocotyledons that you might find are iris, gladiolus, daylily, Easter lily, tulip, hyacinth, autumn crocus, and trilli-um. Some dicotyledons would be rose, pansy, violet, mag-nolia, yellow poplar (tulip tree), morning glory, impatiens,phlox, and tomato. These flowers can be obtained fromeither a garden or a florist.


Direct an investigation. Give your student a flower.(NOTE: For the purpose of this activity a monocot flow-er has been used first. You may begin with either amonocot or dicot flower.) Display page 15 of the HomeTeacher Packet. Use the following statements and ques-tions to guide your student in classifying his flower.

86

Study the chart bdo\\ III compare mOnO,IlI" and dicot-.

Monocots DicotsLeafTubes Go in the Go in all

same direction directions

No. of Flower Groups of 3 Groups ofPetals 4 or 5

No. of Seed 1 2Leaves

Stems soft, hollow woody

75

As your child answers the followingquestions, highlight with a light-col-ored felt-tip pen or put a star besideeach answer on the visual. This willenable your child to easily see whatkind of flower he has when he com-pletes the investigation. Use a differentlight-colored felt-tip pen for the sec-ond flower.

1. Look at the leaves. Do the tubes run in the samedirection or different directions? (same direction)

2. Count the number of flower petals. (a group of 3)3. Look at the stem of the flower. Is it soft and hollow

or woody? (soft, hollow)Continue the investigation. Ask your student to turnto page 75 in his textbook. Allow him to compare thevisual with the chart in his book. Ask him what kind offlower he has. (monocot) Point out the differences be-tween monocots and dicots. Tell him that when mono-cots first sprout they have one leaf called a seed leafDicots have two seed leaves.Conclude the investigation. Give your student a sec-ond flower. Be sure that you do not give indications asto whether the flower is a monocotyledon or a dicoty-ledon. Instruct him to use the chart on page 75 and to

SCIENCE 4 HTE

Flower and Fruit-Producing PlantsPlants that make seeds in flowers and fruits are called

flowering plants. There are some parts that all flowers have.You can see these paris in the drawing below.

The petals arc usually the most colorful part of theflower. God has created many beautiful and colorful petals.

The male part of the flower is the stamen. At the top ofthe stamen arc small pol/en sacs containing the powderygrains of pollen. The female part of the flower is the carpel.The bottom of the carpel is the ovary. A fully developedovary is a/ruff. When you hear the word "fruit," what doyou think of? Do you think of apples. bananas. or grapes')But did you know that tomatoes and corn arc fruit?Cucumbers and squashes are fruits too.

70

observe those characteristics in his flower. When hecompletes his investigation, ask him whether his floweris a monocot or dicot. Tell your student that cotyledonmeans "cupshaped" in the words dicotyledon and mon-ocotyledon. Ask him what he thinks "mono" means.(one) And "di"? (two)

Teaching the LessonDirect a text activity on pages 70-76. Use the follow-ing questions to initiate your student's interest in whathe is going to read.L What is a carpel?2. Do weeds and grasses have flowers?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Look at the picture on page 70. Point to the long

light green part of the flower. What is this partcalled? (carpel) What is located at the bottom ofthe carpel? (ovary)

2. What are the black parts of the flower called? (sta-mens) What is located at the top of each stamen?(pollen sacs containing powdery grains of pollen)

3. How does the pollen get from the stamen to thecarpel? (wind, insects, animals, man)


Inside a fruit are seeds. Sometimes there is only oneseed inside. Can you think of a fruit with only one seedinside' Name some fruits that have more than one seedinside. What wilJ a seed become?

About half of alJ the plants in the world arc floweringplants. Flowering plants can be large or small. Many treeshave flowers, Can you name some trees that have flowers?

71

4. Flowers that are pollinated by insects are usuallyvery colorful and bright Often they have sweetsmells, too. Why did God make the flowers thisway? (to attract the insects) (Bible Promise: L Godas Master) Generally, flowers that are pollinatedby the wind or by animals do not have brilliantlycolored petals. Name some flowers that you haveseen being pollinated by insects. (Answers willvary.)

5. Once the pollen reaches the ovary, what do youthink begins to form? (seed or fruit)

6. Do weeds and grasses have flowers? (yes)Conclude the discussion. Review with your student thefour ways to differentiate between monocots and dicots.You may wish to refer to the chart on page 75 and theflowers he investigated in Introducing the Lesson.

87

Grasses have 11O\\er, 100. They are small and have nocolor. Perhaps you have seen grass flowers and did notknow they were flowers at all.

Botanists have divided flowering plant; into two classes:the monocotyledons and the dicotyledons.

Monocots are flowering plants whose first sprout hasone leaf. This first structure is called a seed leal Dieotshave two seed leaves. Seed leaves have lood in them thatfeed, the tin) new plant.

"I he "cotyledon" part of the words dicotyledon and

nionorotyledon comes from a \\ ord that means "cup-

shaped." What do you think "mono" means'? And "di"?

72

A third way to tell the difference between monocots anddicots is to count the flower petals. Monocots have petalsin groups of three (3, 6, 9, and so on). Dicots have petals ingroups of four or five (4. 5. 8, 10, and so on). Look at thepictures below and decide \\ hich arc monocots and whichare dicots.

74

88

Another way to lell monocots and dieMs apart is tolook at their later leaves. Look at the picture on page 55.

See how the lube, run into the leaves? In a monocotleaf, all the tubes run in the same direction. In a dicot leaf',the tubes run in mall) directions. Are the leaves rnonocotor diem?

The stems of monocots and dicors arc also differentfrom each other. Monocot-, have son. green stems whicharc sometime .. hollow. Dicots have hard woody sterns. Canyou think of a soft-stemmed plant" What would a mapletree be'?

73

Look at the clawification table to see how the plantshave been classified.

plant world

tubes no tubes

seeds tunqr

flowers cones

no seedsI

ferns

algae mosses andliverworts

monocots o.cots

"/fsJ(JI' man, his days are (1,\ grass: as a flower ofthefietd.so heflounshrth," Psalm 11i]:15

76

SCIENCE 4 HTE

name _

Determine whether the ••• re monocotyledons or dicotyledons from their physlca' characterl.tlcl.Circle'" for monacot. and D for dleot •.

MC[) CE> D M CDel9'ilO 8Qb J,;m•• Unl~rolly Prooo. Roproduotlon prOhibited

D Sdence4_book Padcet

Lesson 19

Ev.llialing Ihe Leuon

Evaluating the LessonDirect a notebook activity on page 22. Tell your stu-dent to look at the pictures on the notebook page andto determine whether the picture shows a monocotyle-don or a dicotyledon. Remind him of the physical char-acteristics of each class. Ask him to circle the letter ofthe correct answer.

For Your InformationDicotyledons and monocotyledons are classified un-

der the class Angiosperms. The dicots have approxi-mately 200,000 species classified into more than 250families. The monocots have approximately 55,000 spe-cies classified into more than 40 families.

All the grasses belong to the monocotyledon sub-class. Their flowers look different from what we nor-mally think of as flowers. Instead of having petals andsepals, grasses have many leaflike bracts. (NOTE: SeeFigure 19-1.) Inside these bracts are all the major partsof the flower: the carpel, the ovary, and the stamens.Some grasses are self-pollinated, but wind pollinationis most common.


22

Figure 19-1

Rye grass seed head

spikelet (enlarged)

Fc---- stigma(dangles outside

to collectwind-borne pollen)

anther(dangles outside

to releasepollen into wind)

89

CHAPTER

5Length, Area, and

Volume

Lessons 20-23

Length, Area,and Volume

77


This chapter reviews the measurement of length andthe metric system. Two new concepts, area and volume,are introduced. Your student will learn to find the area ofgeometric shapes using graph paper and will calculate sim-ple areas by using the formula Width x Length = Area.Measuring activities in the lessons provide reinforcementof the metric system for your student.



* 1 large map of the United States] (Lesson 20)* 1 medicine dropper+ (Family Time 21)* Meter stick+ (Family Time 21)* Balance scale with mass sert (Family Time 21)* 2 medicine bottles marked by milliliters (Family

Time 21)* 1 metric weight, from mass set] (Lesson 21)* 1 sheet of centimeter graph paper (Lesson 22)* Graduated cylinder+ (Lesson 23)

91

Lesson 20Length


PreviewObjectives


• Recognize different units of measurement.• Use a scale on a road map.


• A Write It flip chart.• 1 foot ruler.• 1 large map of the United States. *t• 1 paper cube.• 1 brightly colored felt-tip pen.• Home Teacher Packet, p. 20.

Prepare:• The cube using page 20 from the Home Teacher

Packet.

The cube you make in this lesson willbe used again in Lesson 23.


Introduce a demonstration. Ask your student to readRevelation 21:15-16. What city is the verse referringto? (the new Jerusalem) Tell him that God will make anew heaven and a new earth after the thousand-yearmillennial reign. (BAT: 8a Faith in God's promises)Ask your student what the verse is referring to when itsays "the city lieth foursquare."(It is in the shape of asquare. All four sides are equal.)Direct a demonstration. Show your student the modelof the cube you have prepared. Ask him to explain whatbreadth means. (width) Using the cube, show him itswidth. Ask him to measure the width of the cube. Tellhim to write that measurement on the Write It flip chartand label it width. Follow the same procedure with thelength and the height.

92

Direct your student's attention to the cube. Ask himwhether the width of the cube and the length of the cubeappear to be equal. (yes) Tell him that the new Jerusalemwill have equal sides. It will resemble a cube becauseits height, length, and width will be equal.

Now that he has found the measurements of thecube, tell him that he can find the measurements of thenew Jerusalem. Ask your student if he knows how longa furlong is. (220 yards) As you do the problem on theWrite It flip chart, tell him that if he multiplied 12,000furlongs by 220 yards, he would find that the city was1,500 miles long. (NOTE: There are 1,760 yards in amile.) When you have completed the problem, ask himwhat the height and breadth of the city would be. (1,500miles)

Continue the investigation. Display the large UnitedStates map. Direct your student to draw a star on thecity or town where he lives. Show him the scale on themap, discussing how it is used. Explain that the scale isa series of marks placed equally along a line. The scaleof a map allows for accurate measurements on the mapusing a small unit of measurement.

Figure 20-1r------------------ .------------------,

750 miles * 750 miles........--~---...... ..•....------.......IIIIIIIIIIIIIIIIIIL__________________ •

IIIII------------------~

Using the scale on the map, measure 750 miles tothe right, left, top, and bottom of your town. (NOTE:See Figure 20-1.) Make sure that your student places asmall circle on the map to mark the distance. Using thesmall circle to the left and right of your town, have himmeasure 750 miles up and down, placing a dot at eachpoint. Draw a square by connecting the dots. Mark thelines in a brightly colored felt-tip pen. Tell him that thissquare shows how long and wide the new Jerusalemwill be. Remind him that it will also be 1,500 mileshigh.

SCIENCE 4 HTE

"And he that talked with me had a gulden reed measurethe 1'111', and the gUN'S thereof, and the wal! thereo].

And th« city liethfoursouare, and the length is asas the breadth: and he measured the cilY with the reed.(we/vI? thousandfurlongs. The length and thr breadth andthe height ofit are equal," Revelation 21:15 and 16

Length

Suppose that you know that a hemlock tree feettall. Without cutting it down, could use that tree tomeasure distances along the ground. Canway to do that?

Try holding a pencil at arm's length. Line the pencil upwith the edge of the chalkboard or the duo:point down. When the pencil just covers the edgechalkboard or door frame, turn the

think of a

to the floor, keeping the point in theyou measured distance without movingCould you use the sixty-foot tree in the

78

Teaching the LessonDirect a text activity for pages 78-80 . Use the follow-ing questions to initiate your student's interest in whathe is going to read.

1. How accurate is a tree as a tool of measurement?2. How must measurements be expressed?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Would using a pencil and a tree be an accurate type

of measurement? (no) What could account for dif-ferences in your measurements? (slight movementof arm; point of pencil would not remain exactlyin the same place)

2. If you used a tree as a tool of measurement to burya treasure, the person searching for the treasurewould have to use the same tree you did. Whatelse would he have to do just the way you did?(stand in the same place and go the same direction)

3. Would you be able to use the same method to findthe treasure five years later? (no) Why not? (Thetree would have grown.)

4. What types of units could you use? (inches, feet,yards, miles, millimeters, centimeters, meters,kilometers)


How accurate do you think this kind of measuring i~? Ifyou used the tree a tool for measuring. you might tellsomeone to bury a treasure three hemlock-tree lengths froma certain rock, That person would have (0 be sure to usethe same tree vou did. What else would he have to do justthe way you did it" Would you be able to use thc samemethod to find the treasure five years later') Why not"

WELL, BA.BL THISTIME 'IOU l'/\USTA'

79

5. How must measurements be expressed? (innumbers)

6. It is important for scientists to accurately measuretheir findings and results during an experiment.Can you name some different instruments formeasurements that scientists use? (beakers, grad-uated cylinders, thermometers, metric rulers)

93

What other ways are there of measuring length? Howwould you measure the length of your classroom? Wouldyou measure the distance to your house in the same way?How would you report your findings?

Lord Kelvin, a British scientist who lived about 100years ago, said that measurements must he expressed innumbers. Only then. he said. do you know something aboutwhat you arc measuring,

Scientists make many kinds of measurements, and theytry to make them as accurately as possible. AU scientists usethe same ways of measuring. Why do you think they dothat? They can more easily share information and keeprecords.

80

Evaluating the LessonDirect a notebook page activity on page 23. Instructyour student to find the terms describing units of meas-urement in the word search. After he has found thewords, have him write the words under the correct head-ing: Metric or Customary.

For Your InformationLength is defined in the dictionary as the measure-

ment of the total extent of an object along the object'sgreatest dimension. It can be calculated by selecting astandard unit of measurement and laying that unit endto end along the entire distance.

In 1840, the meter was adopted as a standard unitof measure. It was defined as one ten-millionth of thedistance along a meridian from the North Pole to theequator. Since units of measurements are always beingperfected, from 1859 to 1960 the meter was defined asthe length of a platinum-iridium bar located at the In-ternational Bureau of Weights and Measures in France.In 1960, the General Conference on Weights and Meas-ures, which convenes every six years, redefined the met-er as equal to 1,650,763.73 wavelengths of the orange-red radiation of Krypton-86, as measured in a vacuum.This is the standard used today.

94

name _

1. Find the words describing unit. of measurement.2. Place the,. units under the correct he.dlng ..

Metric

I. millimeters

2. kilometers

3. meters

4. centimeters

Customary

I. ounces

2. miles

3. inches

4. feet

5. yards

6. cups

019908obJonesUniversityPr8'Ss I'leproductionprohibited


Lenon 20EVI!u.tlngthoeLflIOI'I 23

SCIENCE 4 HTE

FamilyTime 21Triathlon

Notebook, page 24


• 1 meter stick. *t• Balance scale with mass set.*t• Masking tape or chalk.• I felt-tip pen.• I white potato.• 1 metal teaspoon.• 1 medicine dropper. *t• 2 medicine bottles marked by milliliters. *• A stopwatch+ or watch with a second hand.• 1 object to be weighed.• Home Teacher Packet, p. 17.

Prepare: . .. .• The two medicine bottles by marking millimeter umts

on the outside of each bottle with a permanent felt-tip pen.

• Three medals. (NOTE: See page 17 in the HomeTeacher Packet.)

Your child will be participating in ametric triathlon and will need room tojump. You may want to rearrange theroom or conduct this lesson in theyard.

Instructions -----Set the mood for a metric triathlon. Tell your childthat he will be participating in a metric triathlon. Explainthat a triathlon is an athletic contest in which each con-testant participates in three different activities.

Tell your child that he will have the opportunity tofirst estimate his performance before each event andthen perform the event, comparing the result with hisestimation. Explain that all measurements must be doneusing the metric system.


name _

Triathlon Scores

Estimate Actual Difference

Potato jump

Medicine dropperexchange

Object balance

01990 Botl JOrlH University Presa. Raprodu(:tiOll prohibiled.-O Sdence4

Notebook PacketLesson 21

nadlinQlheL.uofI

Explain to him that one penalty point will be givenfor every centimeter, gram, or millimeter difference(positive or negative) between the estimate and the ac-tual performance of events. The family member withthe fewest points will receive the gold medal. The fam-ily member with the second fewest points will receivethe silver medal, and the third-place winner will receivethe bronze medal.

Set up each of the three areas where the events willbe conducted. Some of the triathlon events may be car-ried on simultaneously.

You will need charts similar to the oneon notebook page 24 for each familymember participating in the triathlon.

Direct the use of notebook page 24. Direct your child'sattention to his notebook page. Show him the first col-umn where he will estimate in metric units his perform-ance for each event. After completing the event, he willfill in the second column showing the actual measure-ment of the event. Finally, in the third column, he willdetermine the difference between Column 1 and Col-umn 2. The total sum of Column 3 will give him hisscore for the possibility of obtaining one of the medals.

24

95

J

i

Direct the triathlon events. Use the following threeevents for the triathlon:Potato Jump Mark a starting line on the floor withmasking tape or chalk. Tell your child to stand behindit. Make sure that his feet do not cross the line. Givehim the handle of the teaspoon to hold in one of hishands. Place a potato on the bowl of the teaspoon. Directyour child to jump forward, with his feet together, asmany times as possible until the potato falls from thespoon. Measure the total distance jumped.Medicine Dropper Exchange Use the stopwatch or sec-ond hand on the clock to time this event for two minutes.Using a medicine dropper, have your child move waterfrom one medicine bottle to another during the allottedtime. Measure the millimeters of water moved.Object Balance You will need an object available forbalancing. Tell your child to try to estimate-by usinghis hand as a balance-the weight of the object in grams.He should record this number on his notebook sheet.Now allow him to balance the object with the gramweights and to record this number on his notebooksheet.Conclude the triathlon. Direct your child to completehis notebook page. Tell him to double-check his addi-tion in Column 3. Award the medals to the family mem-bers with the three lowest scores.

96 SCIENCE 4 HTE

Lesson 21Metrics

Text pages 81-82Notebook, page 25

PreviewObjectives


• Classify measuring units into the metric or U.S. Cus-tomary System.

• Perform measurements using the metric system.


• lone-foot ruler.• 1 yardstick.• 1 pint container.• 1 quart container.• 1 gallon container.• 1 thirty-centimeter ruler.• 1 meter stick.*t• 1 liter container.• 1 metric weight, from mass set.*t• One piece of string, 1 meter long.


Direct an activity. Place the measuring devices listedin the materials list on a table. Ask your student howhe would classify them into two groups. (Answers willvary.) Help him to classify these measuring devices intoa group of metric units and a group of U.S. Customaryunits.

Teaching the LessonDirect a text activity on pages 81-82. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. What system of measurement have most scientists

agreed to use?2. How do you measure around things that are not

fiat?


The system you probably know best is the Englishsystem. It bas units such as inches, feel. yards, miles, pints,quarts, gallons, and tons. These units are sometimes hardto multiply and divide and sometimes hard [0 remember.An easier system to use is the metric Scientists allover the world have agreed to use the metric system.

Measurements of length in this system begin with themeter. A meter is a little longer than a yard. 1.000 metersmakes a kilometer. What do you think kilo- means"

Units smaller than meter the centimeter and themillimeter. Find out what centi- means. What part of ameter is a centimeter'! Find out what milli- means. Whatpan of a meter millimeter?

Which units would you use to measure your foot?Which would you use to measure a fly's wing'! Which twowould you probably use to measure your height'!

8i

97

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. What system of measurement have most scientists

agreed to use? (metric)2. A kilometer is 1,000 meters. What does kilo-

mean? (one thousand)3. Centi- means "one hundredth." What part of a

meter is a centimeter? (one hundredth)4. Milli- means "one thousandth." What part of a

meter is a millimeter? (one thousandth)Conclude the discussion. Remind your student that hemeasured distance, mass, and liquid amounts using themetric system in the triathlon. Ask him how theseamounts were measured. (The distances were measuredusing a straight line. The liquid was measured by mil-liliters. The mass was measured using a balance.) Askhim how he would measure an object that was not flator straight, for example, the globe or trash can. (Answerswill vary.)

Direct his attention to the picture on page 82. Askhim how the child is measuring the tree in the picture.(He uses a string to measure and then measures thestring with a ruler.)

If you have a string and a ruler you can find out howbig around a soda can or a chair leg or even a eat is. Canyou figure out how to measure around things that are not

square?

82

Evaluating the LessonDirect a notebook activity on page 25. Give yourstudent a length of string. Tell him to measure the lengthof his string using his meter stick.

You will need to change any objectsthat you do not have that are listed inthe first column on the notebook page.

Direct your student's attention to the notebook page.Tell him that he will have the opportunity to measureobjects that are not flat using his string. Tell him to listthe object to be measured in the first column. He shouldwrap the string around the object to be measured, mark-ing the place on the string with his fingernail where itmeets the end. Then instruct him to place the string onhis meter stick to find out how many centimeters theobject actually measures. He should then write the num-ber of centimeters in the second column.

98

name _

Using. length 01 string, me •• ure obj.cts In the room and record your finding •.

Column 1 Column 2

globe

trash can

chair leg

file cabinet

01990 Bob Jonn UnlYlralty Pren Reproduclionprohlbiled

D Sdence4NoeeboKP ••••••

L.nIOn21

EVllultlng the l.-on 25

SCIENCE 4 HTE

For Your InformationThe metric system is used by the majority of the

world. The main characteristic of the metric system isthe limited number of basic units. All other measure-ments are derived from this basic unit. For example,length is measured by meters, liquid by liters, andweight by grams. Prefixes are added to describe multi-ples of or smaller divisions of the basic unit. (NOTE:See Figure 21-1.)

Figure 21-1

Units of the Metric System

Length1 kilometer (km) = 1,000 meters1 hectometer (hm) = 100 meters1 dekameter (dkm) = 10 meters1 decimeter (dm) = 0.1 meter1 centimeter (cm) = 0.01 meter1 millimeter (mm) = 0.001 meter

Area1 square kilometer (krrr') = 1,000,000 square meters1 square hectometer (hm") = 10,000 square meters

1 hectare (ha) = 10,000 square meters1 square dekameter (dkm2) = 100 square meters

Volume1 cubic hectometer (hrrr') = 1,000,000 cubic meters1 cubic dekameter (dkm3) = 1,000 cubic meters1 cubic decimeter (dm'') = 0.001 cubic meter

1 cubic centimeter (ern") = 0.000001 cubic meter1 cubic millimeter (rnrrr') = 0.000000001 cubic meter

Capacity1 hectoliter (hi) = 100 liters1 dekaliter (dkl) = 10 liters1 deciliter (dl) = 0.1 liter1 centiliter (cl) = 0.01 liter1 milliliter (ml) = 0.001 liter

Mass or Weight1 metric ton (t) = 1,000 kilograms1 kilogram (kg) = 1,000 grams1 hectogram (hg) = 100 grams1 dekagram (dkg) = 10 grams1 decigram (dg) = 0.1 gram1 centigram (cg) = 0.01 gram1 milligram (mg) = 0.001 gram

The International Bureau of Weights and Measuresmaintains the standards for the units of the metric sys-tem. The meter is defined as 1,650,763.73 wavelengthsof the orange-red light radiated by the isotope Krypton-86, when measured in a vacuum. The gram is definedas one thousandth of the mass of the standard kilogram.The standard kilogram is the mass of a platinum-iridiumcylinder that is equal in height and diameter and meas-ures approximately 3.9 centimeters. The Bureau's re-sponsibilities include developing and maintaining thestandards and perfecting and extending the metricsystem.


Lesson 22Area

farm, it became a rectangle. How could Joseph doublehis farm but keep it in the shape of a square?Direct the activity. Place the first prepared square infront of your student. Tell him that this square willrepresent Joseph's farm. Now place the second squarenext to the first. Ask him what shape is made. (rectan-gle) Show him that wherever the second square is placednext to the first square, the shape is still a rectangle.

Allow your student the opportunity to "brain-storm," discussing how Joseph can double his farm yetretain the shape of a square. Discuss the possibilities ofdividing the square into four smaller squares. Demon-strate with the square cut into four equal squares that itwill not work. (NOTE: See Figure 22-1.)


PreviewObjectives Figure 22-1


• Measure the length and width of objects using themetric system.

• Calculate the area of an object.


• A Write It flip chart.• 4 paper squares (10 em x 10 ern).• 1 metric ruler.• 1 sharpened pencil.• I sheet of centimeter graph paper.*• Several flat objects to measure.

Prepare:• The four paper squares by leaving two whole, cuttingone into four equal squares, and cutting one diago-nally into four triangles.

Conclude the activity. Ask him what other shapes hemight try. Discuss the possibilities of dividing thesquare into four triangles. (NOTE: See Figure 22-2.)Allow him time to try an arrangement.

This lesson calls for using graph paper.Since the metric system is being em-phasized throughout this chapter, youwill want to have centimeter graph pa-per available.

Figure 22-2


Introduce the activity. Tell your student that JosephHillard was a farmer who was struggling to raise enoughfood to feed his wife and six children. Because of Jo-seph's willingness to share his home and food, the kingwanted to reward him. He promised to grant the farm-er's wish to have the size of his farm doubled with onecondition: the farm must remain a square when it wasdoubled. The farmer knew his farm was 200 meterssquare, but when he added the same size square to his

100 SCIENCE 4 HTE

Guide him to try placing the four triangles on eachside of the square. These added triangles will make thesquare diamond shaped. Ask him to turn the square withthe triangles showing that the farm is still square.(NOTE: See Figure 22-3.) Ask him if Joseph has dou-bled his farm and still kept the shape of it a square.

Figure 22-3

r····························· -.-.-.-.···.-.---···---------1


AreaHow big is the front of your notebook? Do you know

bow to find out? The surface of the front of your notebookis the area. If you measure the width and the length andmultiply those two measurements together, you will comeup with the area of the notebook.

AREA= WIDTH X LENGTH

Suppose the notebook is twenty-five centimeters wideand thirty centimeters long: You need (0 multiply 25'by 30'to find the area: What is the answer'? You. should get thenumber 750. But 750 what? It cannot be centimetersbecause centimeters measure only along a.Iine=-not an )area. We say a line is one-dimensional; it has only length.An area is two-dimensional. What does it have'?

The area of the notebook is 75.0 squarecentimeters ..Area is always expressed in square units.

83

Teaching the LessonDirect a text activity on pages 83-84. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. What is the formula for finding the area of a square

or a rectangle?2. How should the answer be expressed?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. What is the formula for finding the area? (Area =

Width x Length) Write the formula on the Write Itflip chart.

2. What is the width of Joseph's farm? (200 meters)Write this number underneath the word width onthe flip chart.

3. What is the length of Joseph's farm? (200 meters)Write this number underneath the word length onthe flip chart. Work the equation to find the areaof the farm. (40,000)

4. How should the answer be expressed? (square me-ters) Add square meters to the answer on the flipchart.

5. Look at the pictures on page 84. How many squarecentimeters are in these pictures? (top le/t-4; topright-6; bottom lejt-9+; bottom right-10)

101

If tad, Gluck is one square centimeter, how manysquare centimeters are in these pictures?

84

/'

102

About Length and AreaL Get a ruler, a pencil. graph paper. and several flat

objects to measure.

2. Measure the length and width of all the objects. Recordyour findings.

3. Draw around one of the flat objects on the graphpaper. Determine the area represented on the graphpaper. Now find the area by multiplying the length andwidth of the object. Record and compare your findings.

85


During the Finding Out activity, yourchild should use centimeters for themeasurements.

Gather the materials for the Finding Out activity onpage 85. Give your student a pencil, a metric ruler, andone sheet of centimeter graph paper. Tell him that hemay measure his textbooks, notebook, and any other flatobjects he finds.

SCIENCE 4 HTE

name _

WidthObject Length

I Length X Width = Area I

________ X _

Counted squares: _

Calculated squares: _

C>'!i9(l Bob Jones Universi!y p,,",. Reproduction prohlbll&d

D Sdence4N_book Packet

Lesson 22EYIIlultinlltheLeuon

Direct the use of notebook page 26. Tell your studentthat after he measures the length and width of eachobject, he should record these measurements on thenotebook page.

Ask him to choose one object for which he wishesto find the area. Tell him to trace the outline of theobject on graph paper. Instruct him to count the numberof squares within the pencil lines. Tell him to write thisnumber on the bottom of his notebook page. Now havehim calculate the area of the outline by measuring thewidth and length and then multiplying those measure-ments. Tell him to write this number in the proper placeon the notebook page. Ask him whether the two num-bers are the same. (Answers will vary.)


26

For Your InformationArea is always expressed as a number. This number

tells how many standard units of measurement are inthe region that is being measured. Two standard unitsof measurement are the square inch and the square cen-timeter. The area can be calculated either by countingthe total number of standard units in a region or byusing the following formula.

Width x Length = Area

103

Lesson 23Volume

Text, pages 86-90Notebook, pages 27-28

PreviewObjective


• Calculate the volume of regular polygons.


• A Write It flip chart.• Prepared cube from Lesson 20.• Graduated cylinder.*t• A small amount of water.• 1 small stone.• 1 blue crayon.• 1 yellow crayon.


Introduce the activity. Ask your student what a one-dimensional figure would be. (a line or a figure that hasonly length) What would a two-dimensional figure be?(a figure that has area) Display the cube you made inLesson 20. Ask your student what dimension he thinksthe cube is. (three-dimensional) Why do you think it isthree-dimensional? (It has length, width, and height.)Ask your student what formula he used to find the areaof a figure. (Area = Width x Length) Explain to himthat the amount of space a three-dimensional figuretakes up is called volume. Ask him what formula hecould use to find the volume of a three-dimensionalfigure with length, width, and height. (Volume = Lengthx Width x Height) Write this formula on the Write Itflip chart. Instruct your student to measure one side ofthe cube. Tell him to insert the numbers in the equation.(NOTE: All the numbers will be the same since theobject is a cube.) Compute the volume of the cube.Direct a notebook activity on page 28. Using the for-mula at the top of the page, instruct your student tocalculate the volume of the objects listed. Work through

104

name _

Calculatf! Ihf! volume 01 the following object •.

ILe';gth X Width X Height = Volume I

1= 10w = 5h=6volume = _-,3",,0,,-0 _

1=5w= 3h=4volume = __ 6_0__

,..~,w= 2h=3volume = _--=36:.....-_

C].1=9w = 3h=6volume - _"",,16=2 __

w = 3h=6volume =_-,-,,19-=..8 __

01990BobJoneIUn;~r$;!yPress Reproductlonprohibiled

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lesson 23

28

the first example with him, telling him that he shouldmultiply the first two numbers, and then multiply thisproduct and the last number to find the answer. If he ishaving difficulty with multiplication, you may want tocomplete the entire page together or allow him to use acalculator. The purpose of this page is not to learn mul-tiplication but to learn how to find the volume.

SCIENCE 4 HTE

VolumeWhich figure has three dimensions" Do you think you

can find out how much space it takes up? The space itoccupies is called ib volume.

What doc, the three-dimensional figure have that thetwo-dimensional one docs not? It has height or depth.What measurements do you think you multiply together tofind the volume?

VOLUME = LENGTH X WIDTH X HEH;HT

If you have a box that is ten centimeters "ide and tencentimeters high and twenty centimeters long. you have abox that has a volume of 2.000 cubic centimeters. Volumeis always expressed in cubic units.

86

Teaching the LessonDirect a text activity on pages 86-89. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. What was Archimedes' solution to finding the vol-

ume of an object that did not have smooth, regularsides?

2. Did the artist cheat the king when he made theking's crown?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Look at the pictures on page 86. Which objects are

one-, two-, or three-dimensional in the picture?(The line is one-dimensional, the square is two-dimensional, and the cube is three-dimensional.)

You may wish to reinforce the conceptof dimensions by guiding your child'sattention to various objects in theroom. Ask him to determine each ob-ject's dimension by holding up one fin-ger for one-dimensional objects, twofingers for two-dimensional objects.and three fingers for three-dimensionalobjects.


What would happen if you tried to multiply meters andcentimeters' What would you get'? To find volume or area,you have to use measurements expressed in the same units.

Not all objects have smooth. regular sides. How do youthink you could find the volume of a stone? Or a goldcrown? A mathematician in ancient Greece namedArchimedes was given a similar problem.

King Hieron II had ordered an artist to make him acrown of pure gold. !lut when the crown arrived, the kingsuspected that the artist had cheated him. He askedArchimedes to find out whether the crown was pure goldwithout destroying the crown. Archimedes thought andthought about it. There seemed no way to test the goldwithout heating it or damaging the crown.

One day while sitting in a bath, Archimedes noticed thatthe water level went up when something was immersed in it."Eureka!" he cried. He had found the answer. Do youknow what it was?

87

2. What did Archimedes discover while taking abath? (that objects displaced, or pushed away, wa-ter) Can you name some examples of liquid dis-placement? (putting dishes into a sink full of wateror ice cubes into a glass of lemonade)

3. What was Archimedes' solution to finding the vol-ume of an object that did not have smooth, regularsides? (He weighed a small piece of gold andplaced it into a container filled to the brim withwater. He measured the overflow water to calcu-late the volume of that piece of gold.)

4. How did Archimedes find out that the artist hadcheated the king? (He calculated what the volumeof a solid gold crown should be. He immersed theking'» crown in water and found that it displacedtoo much water to be made of solid gold.)

105

Archimedes took a piece of gold he knew was pure andimmersed it in water. Then he measured how much waterhad been moved and weighed the water. By comparing the

weight of the gold with the weight of the water that movedup when the gold was put in, he found out how much waterreal gold should move or displace,

~Ihe mathematician took the crown and tested it thesame way, What do you think he found? He found that theartist had indeed cheated the king, He had kept some of thegold for himself and made part of the crown from silver.

88

You may wish to explain to your childthat Archimedes discovered more thanthe volume of the gold. He also de-rived the principle of buoyancy. Buoy-ancy is the upward push placed on anobject in a liquid or in a gas. Buoyancyallows something or someone to re-main afloat. Your child uses this prin-ciple of buoyancy while swimming.

5. Look at the last paragraph on page 89. Calculatewhat the volume of the plastic toy is. (57 cu. em -50 cu. em = 7 cu. cm) The amount of milliliters anobject displaces in a graduated cylinder is equal tothe object's volume. (l milliliter = I cubiccentimeter)

106

Archimedes was looking for more than a simple volumewith his test. but you can use the same idea to find thevolume of objects that do not have smooth, easy-to-measure sides,

An object that is completely immersed in water "illdisplace a volume of water that is the same a~ its ownvolume, Suppose you put water into a graduated cylinderuntil the lowest point is fifty cubic centimeters. Then youput in it small plastic toy, The lowest part of the water nO\I

is at fifty-seven cubic centimeters. What is the volume ofthe toy?

89

Evaluating the LessonDirect a Finding Out activity un page 90 and note-book page 27. Ask your student to read page 90 beforebeginning this activity. Place the graduated cylinder,water, and small stone in front of your student. Ask himto pour a small amount of water into the graduatedcylinder. Instruct him to read the number of millilitersby reading the markings at the lowest curved part of thewater. (NOTE: See Figure 23-l.)

Instruct your student to write the number of milli-liters on his notebook page next to the words waterlevel. Allow him to color in the first drawing of thegraduated cylinder on the notebook page. He should usehis blue crayon and color the graduated cylinder fromthe water level to the bottom of the cylinder.

Ask him to carefully drop a small stone into thegraduated cylinder. Instruct him to read the millilitermarkings. Write this number beside the words stoneadded on his notebook page. Allow him to mark thisnumber on the second drawing of the graduated cylin-der, coloring it with his yellow crayon.Conclude the demonstration. Direct your student tothe subtraction problem at the bottom of the page. Ex-plain to him that the difference between the first waterlevel and the second water level is the volume of thestone.

SCIENCE 4 HTE

About Volume

I. Get a graduated cylinder. water, and a small stone.

2. Pour some water into the cylinder. Take a reading atthe lowest curved part of the surface of the water.

3. Place the stone into the water. Be sure the watercompletely covers the stone. Take another reading atthe lowest curved part of the surface of the water.

4. Subtract the first reading from (he second. Record thevolume of the stone.

90

Figure 23·1


name _

I _ Mark on the first graduated cylinder the amount ofwater used. Color with a blue crayon to that mark.

2. After the stone has been submerged, mark the newwater level on the second graduated cylinder. Colorwith a yellow crayon to that mark.

3. Calculate the volume of the stone.

water level: _

stone added: _

volume of stone: _

'1990 Bob Jontl Unlvlrlily Preu. Reproductlonprohlblt..:!.

te ••on 23

T•• chlll9 tI\.lanon

For Your InformationArchimedes' talents were varied. His practical in-

ventions included a simple machine that would raisewater from the Nile River to irrigate the fields. He in-vented military weapons such as catapults, missilethrowers, and grappling hooks to aid against enemyattacks.

His mathematical and scientific discoveries were sogreat that he has been called the greatest scientist priorto Newton.

The traditional account of Archimedes' death is asfollows. Roman soldiers invaded Syracuse, the citywhere Archimedes lived, in 214 B.C. For approximatelytwo years, the Greeks were able to defend their city. In212 B.C. the Romans finally gained the advantage. Withfighting going on all around him, Archimedes sat in themarketplace concentrating on some geometric shapeshe had sketched in the dirt. As a Roman soldier ap-proached him, Archimedes yelled, "Disturb not my cir-cle. " The Roman soldier ignored his command, killingArchimedes where he sat.

107

27

CHAPTER

6Digestion

Lessons 24-27

Digestion

91

This chapter presents the five main parts of the diges-tive system: the mouth, the esophagus, the stomach, thesmall intestine, and the large intestine. As your studentstudies each part, he will construct a representation of thatpart. By the end of Lesson 27 he will have assembled amodel of the route that food takes through the digestivesystem.



* 1 lemon (Lesson 24)* 1 orange segment or apple slice (Lesson 24)* Vacuum-cleaner hose (Lesson 25)* 2 or 3 cups of finely chopped vegetables and/or fruits

(Lesson 26)* 1 package of unsweetened Kool-Aid (Lesson 27)

SCIENCE 4 HTE

Lesson 24The Mouth

when he thinks of digestion. (Students usually identifythe stomach first. Answers will vary.) Display page 18of the Home Teacher Packet. Point out that the first partof the digestive system is the place where the food goesinto the body-the mouth.


The digestive tract visual found on

'C ,-_p_ag_e_l_8_0_f_t_h_e_H_om_e_T_e_a_c_h_e_r"".will be used in Lessons 24-27.

Your child will look at the diagram ofthe tongue on page 94, but he will notdo any activities involving isolatingthe parts of the tongue that sense spe-cific tastes until Lesson 27. At thattime, he will refer to the diagramagain.

Direct the activity. Give your student a cracker. Tellhim first to take a bite of the cracker and hold the piecein his mouth for thirty seconds before chewing it andswallowing it. Signal the end of the thirty seconds; thenask him what happened to the cracker as he held it inhis mouth. (It started to get soggy.)

Give your student an orange segment or an appleslice. Before letting him eat the fruit, tell him to con-centrate on what his teeth and tongue do as he chewsand swallows the fruit. After he has eaten the fruit, askhim what his teeth did. (chopped, crushed, and groundthe fruit) Ask him what his tongue did. (Your studentmay not name all the things a tongue does, but bycontinuing to ask him questions you can draw out allthese answers: The tongue moved the food around inthe mouth, held it near the teeth, and rolled it aroundto be chewed all over. Then it pushed the food towardthe back of the mouth to be swallowed. It also detectedthe flavor of the food.) Ask him to describe the flavorsof the cracker and the fruit. (Answers will vary.)Conclude the activity. Set the lemon, the knife, andthe glass where your student can see them. Slice thelemon and squeeze some juice into the glass. Then askhim to tell what happened in his mouth as he watched.(His mouth started to water.) Ask for the name of the"water" that started to form in his mouth. (saliva orspit) Finally, ask why the saliva started to fonn whenhe saw the lemon. Allow him to give his ideas, but donot comment on them at this time. Pages 92 and 93 ofthe student text will explain saliva's part in digestion.

PreviewObjectives


• Identify the tongue as the part of the mouth thatmoves food around.

• Identify the teeth as the part of the mouth that breaksfood into small pieces.

• Identify saliva as a liquid in the mouth that softensandmoistens the food and changes some starches intosugar.


• A Write It flip chart.• llemon.*• 1 knife.• 1 drinking glass.• 1 cracker.• 1 orange segment or apple slice.*• Home Teacher Packet, p. 18.


Introduce the activity. Tell your student that today'slesson is the first of four lessons about digestion. Ex-plain that during these lessons he will study the parts ofhis body that God designed especially for changingfood-like an apple or a cracker-so that his body canuse it. Ask him what part of the body he thinks of first


Did you know your digestive system is rather like afactory? II lakes in material, makes useful products, anddistributes them. Some part of this factory is alway'operating, and rarely do the worker> fail to do their work.The factory is one of the most efficient and inexpensive tooperate. And what it produces for your body is extremelyvaluable.

What is your favorite food? Think of taking a bite of itright now . Just thinking about a food you like can set thefirst stage of digestion going. LOOking at food or smelling itcan also cause this process to begin. Can you guess whatthe first part of digestion is!

92

Teaching the LessonDirect a text activity on pages 92·94. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. Why did the saliva start to form when you saw the

lemon?2. Find the meanings of the words enzymes, ptyalin,

and bolus as you read. (NOTE: Write these wordson the Write It flip chart and pronounce them cor-rectly for your student before he begins to read:enzyme [en'zirn], ptyalin [ti'a-lln], and bolus[bo'Ics]. )

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Why did the saliva start to form when you saw the

lemon? (The sight-and perhaps the smell-of thelemon set off the first stage of digestion: the pour-ing of saliva into the mouth.)

2. What are the jobs of the saliva? (to combine solidfood with liquid to make swallowing easier, to al-low thefood [now in liquidform] to reach the tastebuds, and to change some food into sugar.)

110

The MouthGlands in the cheeks near the cars and below the tongue

pour saliva into the mouth. TIley produce about a quart ofsaliva a day. Without saliva. food would not get softenough to swallow easily and you would not be able totaste anything. Even when you are not eating, saliva usuallykeeps your mouth moist inside.

Saliva contains ptyalin. one of the many eml'll/('s thatglands in the body make to help digest food. Bread,potatoes. and corn arc foods that ptyalin works on as youchew. It turns the starch in them into sugar. Meats and fatsare not changed into sugar by saliva. But the more salivaany food has in it the better it forms a small ball, or bolus.for swallowing. Why do you think it is important to chewyour food well before you swallow'!

Your tongue and your teeth are also essential to gooddigestion. The tongue pushes food around inside themouth; it moves the food so that the teeth can crush it intosmall pieces. The tongue also has another job, one youprobably think is more important. lt lets you taste yourfood.

The importance of changing somefoods (starches) to sugar in the mouthmay not be clear to your child. To himsugar means only "sweetness." Butsugar dissolves in water, whereasstarch does not. The ptyalin in salivachanges starch to sugar in the mouthand sends it on its way to the stomachwith the digestive process alreadyunderway.

3. What is an enzyme? (An enzyme is a substancethat glands make to help digest food.)

4. What is ptyalin? (Ptyalin is an enzyme that changessome foods into sugar.)

5. What is a bolus? (A bolus is a small ball of foodformed just before swallowing.)

6. What four kinds of taste does the tongue detect?(sweet, salty, sour, and bitter)

7. What kinds of things cause tooth decay? (food,saliva, dead cells, and bacteria, which make anacid that causes cavities in the enamel)

SCIENCE 4 HTE

93

tongue

sweet

The tongue has about ten thousand taste buds. specialorgans that react to chemicals. The tongue can detect fourkinds of taste: sweet, salty. sour. and bitter. Taste buds thatpick up sweet flavors are on the tip of the rongue. Salty andsour detectors arc usually along the sides: taste buds thatreact to bitter tastes are along the back, What else doesyour tongue help you do'!

You need to take good care of your teeth because theybite and grind all the food you eat. The front teeth cut andtear; the side and back teeth grind and crush, If you do notcare for your teeth, bits of food. saliva, dead cells. andbacteria will build up on them, As the bacteria grow inthese conditions, they make an acid that cats holes, orcavities, into the enamel. Have you ever had a hole in yourtooth filled? What did the dentist replace the enamel with?

When you decide you have chewed your food enough,the tongue forms it into a bolus and pushes it toward theback of your throat. Up until now. vou could still spit thefood out. But once you start to swallow. your body takesover and you must swallow.

94

Conclude the discussion. Ask your student to describehow he takes care of his teeth. Discuss the importanceof brushing after eating and of flossing the teeth daily.Your student will have a variety of answers for thequestion about the materials used for fillings. For theside and back teeth where grinding and crushing takeplace, most dentists use an amalgam of silver and mer-cury. For the front teeth, where an amalgam would bevisible, dentists use a white composite filling material,which they match as closely as possible to the color ofthe person's own enameL

You may wish to schedule a visit tothe dentist for your child at this time.He will be able to see the various typesof fillings used and will learn whetherhe is brushing thoroughly.


name _

The MouthComplete the sentenc •• by telling what each part or the mouth dO.1 to begin Ihe dlgeltlve proce •••

moves food aroundThe tongue _In the mouth.

softens and moistens foodSaliva __ --:-~----~--

and changes some

starches to sugar.

Salivary Glands

Teeth break food into small pieces.

Wording may vary,

'19!1O BOb Jones Unlve"ily Pr•••. R.productlonprotllblted.

teeecn 24

Evalualinlil1h.Lflton

Evaluating the LessonDirect a notebook activity on page 29. Instruct yourstudent to follow the directions to complete the sen-tences on the page.

For Your InformationSaliva is 99 per cent water and 1 per cent ptyalin

and salts. It pours into the mouth from three pairs ofsalivary glands. The parotid glands lie below and some-what in front of the ears. The saliva from the parotidglands is carried into the mouth by a duct that opensnear the upper molar teeth.

The submaxillary glands pour saliva into the mouththrough ducts that open at the midline of the base of thetongue, along the floor of the mouth. A person may findthe approximate location of these glands by drawing hisfingers down from the outer ends of his eyebrows, overhis cheeks, and just below his jawbone.

The sublingual glands are located beneath the frontof the tongue and supply that area of the mouth withsaliva. Sometimes those glands are activated when aperson yawns. If at that time, he inadvertently curls uphis tongue, he may surprise himself (and anyone in frontof him) by spraying saliva from his open mouth,

111

29

Lesson 25The Throat


Objectives

Prepare:• The "mouth" for the model by cutting out red paper

lips and taping them to the bowl.• The "esophagus" and "trachea" for the model. Tape

the cardboard tube (the trachea) to the top of thevacuum cleaner hose. Cut a small piece of red con-struction paper to cover the opening of the tracheaand tape it so that it can flap open or shut. This flapwill represent the epiglottis. At the back of the card-board tube, tape two partially inflated balloons, rep-resenting lungs. (NOTE: See Figure 25-1.)

• The bottle by labeling it saliva.• The sphincter and peristalsis shapes by cutting them

from page 19 in the Home Teacher Packet.

Preview


• Identify the parts of the esophagus.• Define peristalsis.


• 1 bowl (soup or cereal).• 1 piece of red construction paper.• 1 cardboard tube from paper towels or wrapping

paper.• 2 small balloons.• 1 vacuum-cleaner hose. *• Transparent tape.• 1 quart bottle filled with water.• 1 label.• 1 felt-tip pen.• 2 flexible drinking straws.• Home Teacher Packet, pp. 18-19.

NotesThe model that is begun in today's lesson will be added

to in the next two lessons. You may want to refer to thematerials lists for those lessons to gather the items now forthe whole model.

In their earlier literature about the Heimlich Maneuver,the American Red Cross recommended that the victim leanover while the maneuver was being given. However, thatposition is no longer suggested. The upward thrust hasproved to expel an obstruction with sufficient force so thatthere is no danger of the object's falling back into thevictim's mouth.

Figure 25-1

bowl

P'P"Ii"~

112 SCIENCE 4 HTE

LessonIntroducing the Lesson ---

Introduce a model-building activity. Place in front ofyour student the materials for beginning the model ofthe digestive system. Explain to him that beginning witha review of the first part of the digestive system-whichhe studied in Lesson 24-he will build a model as hestudies each part.Conduct the activity. Ask your student where digestionbegins. (in the mouth) Hold up the small bowl with thelips taped to it. Ask him to name the things in the mouththat aid in digestion. (teeth, tongue, saliva) Ask him toname the ways that the teeth function. (Biting, tearing,crushing, and grinding work together to break solidfood into tiny pieces before it is swallowed.)

Ask for an explanation of how the tongue aids inthe breaking up of food. (It moves the food around inthe mouth so that the teeth can chew the food thor-,oughly.) Then ask what else the tongue does. (It allowsa person to taste the food, and it moves the food to theback of the mouth to a position where it can beswallowed.)

Ask your student what part the saliva has in diges-tion. (moistening thefood and changing somefoods intosugar in the mouth) Why is it important that starchesbe changed into sugar? (Sugar dissolves in water, butstarch does not.) Set the bottle labeled saliva beside thebowl and ask your student to aid you in placing one endof a straw into the bottle marked saliva and the otherend into the bowl. (NOTE: He may need to connect twostraws at the inflexible end to reach both the opening ofthe bottle and the bowl.)Continue the activity. Hold up the vacuum-cleanerhose with the trachea and lungs model attached to it.Explain that this piece represents a part of the digestivesystem that he will study in this lesson. Place the hoseon the table, and direct him to his reading assignment.

You will want to put the model whereyou can continue to work with it dur-ing this lesson and the next twolessons.

Teaching the LessonDirect a text activity on pages 95-98. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. How would you use the materials on the table in

front of you to add to the model of the digestivesystem?


The ThroatIf you eat too fast or if you try to talk as you swallow.

you may get something "down the wrong throat." What doyou think that means? You really have only one throat, thepharynx: but it branches into a windpipe and a food pipe alittle below the back of the mouth. The windpipe is calledthe trachea. and the food pipe is called the esophagus.Where the pharynx branches there is a valve that closes offthe trachea when you swallow. If you swallow too fast. thevalve sometimes does not get closed and some food goesdown your trachea. Then what happens"?

pharynx

esophagus

95

2. What is the process of peristalsis?3. What is the sphincter?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Look at the model of the digestive system. Add the

hose correctly to the model. (He should put the"trachea" end of the hose into the bowl.)

2. What does the cardboard tube represent? (the wind-pipe or the trachea) What does the windpipe do?(The windpipe allows air to go into the lungs.)What part of the model represents the lungs?(balloons)

3. Look at the small flap. What does this flap repre-sent? (epiglottis) What is the job of the epiglottis?(to prevent food from entering the windpipe whena person swallows)

4. If food does enter the windpipe, the person maychoke. What do you do when someone chokes onfood? (Stand behind the person and place yourarms around him. Put your fist below the middleof his ribs. Then, putting your other hand over yourfist, press in quickly.)

113

If food goes down your trachea. \OU cough. If the foodcompletely blocks the trachea. you choke. Do you knowwhat to do if someone cannot breathe because food J1<blodged in his windpipe" You should stand behind him andstretch your arms around him. Put your fist just below themiddle of his ribs. Then. putting your other hand over ,ourfisc press in quickly. The sudden rush of breath going outcan move the food out of the trachea. You should never trythis on your own. Let a trained adult help )OU

96

You may wish to tell your child thatthis procedure is called the HeimlichManeuver. Because the Heimlich Ma-neuver may cause injury, stronglywarn him not to practice it on anyone.

5. Look at the prepared words peristalsis and sphinc-ter. What do the muscles of the esophagus do inthe process of peristalsis? (The muscles squeeze inabove the food and move it along toward the stom-ach.) In a similar manner, something is squeezingin on the letters of the word.

The esophagus is a short tube that carries food intoyour stomach. The esophagus has a tough lining thatprotects the muscles. and it can stretch wider than it>

normal size. Why are these two characteristics importantfor a food pipe?

The muscles of the esophagus contract in waves to movethe food into the stomach. These muscles arc so strong thatyou can swallow even while standing on your head. Themovement of the muscles is called peristalsis. The namecomes from two Latin word parts that mean "to ,naparound." The muscles squeeze in above the bolus. pushingit along. The next group of muscles then squeeze in abovethe boll" and so on. The muscles continue to "wraparound" the food in this way until it passes into thestomach. The process is something like working a marblethrough a rubber hose by pinching the hose together abovethe marble.

peristalsis

97

6. What does the sphincter do? (The sphincter pinch-es the esophagus shut at the top of the stomach,just as the last letters of the word are beingpinched.)

7. Allow your student to attach these two words tothe model. (NOTE: See Figure 25-2.)

Conclude the discussion. Tell your student that theperistalsis allows him to swallow food while he is lyingdown or even standing on his head. Display page 18 ofthe Home Teacher Packet. Point out the esophagus inthe diagram and tell him that the food's trip along theesophagus takes about 8 seconds.

Figure 25-2

114 SCIENCE 4 HTE

At the bottom of the esophagus arc some strongmuscles. They can pinch together. The opening thesemuscles control is called a sphincter, \\ hich come:') from a

word that means "to bind tightly." Is that a suitable name'!Why docs the food pipe need to he closed at the top 01 thestomach') Without such a valve, food might rise back upwhenever you bend over. jump up, or eat too much.

98

Evaluating the LessonDirect a notebook activity on page 30. Instruct yourstudent to follow the directions on the page and to com-plete the diagram of the second part of the digestivesystem: the esophagus.

For Your InformationThe act of swallowing consists of several events that

occur almost simultaneously. When the food bolus isready to be swallowed, the teeth come together, and thetongue moves upward and backward along the roof ofthe mouth to push the food into the pharynx. Before thefood begins to move into the pharynx, the tip of the softpalate (uvula) pushes back and up to close off the pos-terior opening of the nose. This closing prevents foodand beverage from coming back out through the nose.If a person laughs with food or drink in his mouth, theuvula relaxes, and the rush of air from the lungs mayblow the food or drink into the back of the nose.

Also, during swallowing, the muscles of the pharynxconstrict and direct the food bolus toward the esopha-gus. The cartilage flap (epiglottis) at the top of the lar-ynx bends down and back to close the opening to thetrachea (windpipe). This closing prevents inhalation offood and makes it impossible for a person to breathe


name _

The EsophagusL.bellhe numbered part. In the diagram of the second pari of the digestive Iy.tem. You may cheesefrom the words betow.

bolusepiglottis

esophagusperistalsis

salivary glandstrachea

trachea

2. ec:..::s-"op,-h_a,,-gu--,-s_

3. __ -"b..:..O/..:..us"---__

The diagram below llIult,ates ".rl.,.,~•.Explain what hap~ns during perl,talsls.

During peristalsis, wavelike muscle

movements move food along the esophagus to

the stomach. (Wording may vary.)

DIIIIIO Bob Jon" Unlver,Jt.,. Pr•••. ReproducUon prohibited.

D Sdence4Noeobook Padolt

J.eQOn25EVlh.lltlnglhll.neon

while swallowing. At that very moment, the esophagusis dilated to receive the food bolus. The upper portionof the esophagus contains skeletal muscle tissue forrapid peristalsis, and the lower portion has visceral mus-cle tissue that contracts more slowly. The lining of theesophagus is smooth and well lubricated with mucus toprovide efficient transport of food to the stomach. Thesphincter muscle between the esophagus and the stom-ach is relaxed at this time to allow food to enter thestomach easily.

115

30

Lesson 26

Materials

The StomachText, pages 99-1 01

PreviewObjective ------


• Identify statements about the digestive functions ofthe stomach as true or false.

Have available:• The model of the digestive system as far as you con-structed it in Lesson 25.

• Home Teacher Packet, p. 18.• 1 blender (or a dishpan).• 1 quart bottle filled with water.• 1 label.• 1 felt-tip pen.• 2 flexible straws.• 2 or 3 cups of finely chopped vegetables and/orfruits.*

Prepare:• The bottle by labeling it "gastric juices."

Figure 26-1

Conduct a demonstration. Tell your student that dur-ing the 1 to 6 hours that food spends in the stomach, itchanges quite drastically from the form it had when itwas swallowed. Show him the chopped vegetables andfruit that you have prepared, emphasizing that they havebeen chopped up and "chewed" in the mouth and areready for the stomach. Remove the end of the vacuumhose and the end of the straw from the blender jar andput the chopped-up food in. Explain that you must addsome gastric juices before you can turn the "stomach"on; then pour about one-fourth cup of water from thebottle into the blender jar. Put the lid on and turn on theblender, allowing the mixture to blend until it becomesa "soupy" liquid like the contents of the stomach afterthe gastric juices and peristalsis have done their work.Show the contents of the blender to your student andexplain that in the stomach, this soupy liquid is calledchyme [kim]. Then "reconnect" the vacuum hose andthe straws to the blender.


Continue the model of the digestive system. Pick upthe sphincter end of the vacuum cleaner hose and put itinto the blender jar. (NOTE: See Figure 26-1.) Ask yourstudent what part of the digestive system he thinks theblender represents. (the stomach)

Hold up the bottle labeled gastric juices. Explainthat the gastric juices consist of water, hydrochloricacid, and enzymes. Gastric juices come from the glandsthat line the stomach. The glands begin to make thejuices when a person tastes, smells, sees, or even thinksabout food. Ask your student if he remembers anotherliquid that starts to form when a person thinks aboutfood. (saliva) Allow him to extend a straw from thebottle labeled gastric juices to the blender jar. (NOTE:He may need to connect two straws at the inflexible endto reach both the bottle and the blender.)

For safety, remove the blender jar fromits base after finishing this demon-stration.

116 SCIENCE 4 HTE

The StomachThe stomach is probably the first thing you think of

when you think of digestion. But as you can see, it does notfunction until digestion is well under way. Where do youthink your stomach is?

Many people think that the stomach is right in themiddle of the body. But it is higher, just below the ribs. It isabout the size of your two fists. Did you think it was biggerthan that?

The stomach is mostly a storage bag, a bulge in the foodtube. that acts on food in the ways that the mouth does.What are the two ways that the mouth works on food" Itworks on it mechanically by moving it around, and it workson it chemically, changing and breaking food down intodifferent parts.

99

Teaching the LessonDirect a text activity on pages 99-101. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. Why does your stomach sometimes rumble?2. How does your stomach chum food?3. How does the stomach acid keep from digesting

the stomach itself?Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. How big is your stomach? (about the size of a

person's two fists)2. Where is your stomach located? (just below the

ribs)3. Why does your stomach sometimes rumble? (The

noise is caused by the food churning around in thestomach.)

4. How does your stomach churn food? (byperistalsis)

5. What is different about the way the stomach chopsfood and the way we made it in the blender earlier?(The action of the stomach muscles-peristalsis-isa squeezing action, but the action of the blender isa spinning, cutting action.)


Does your stomach growl sometimes? You probably saythat you are hungry whenever that happens. But yourstomach can rumble even when it has food in it. Yourstomach churns food by peristalsis, the muscles around themiddle and lower part squeezing much like the esophagusmuscles. Because the stomach nearly always has some air,or gas. in it. the churning food sometimes sloshes aboutand creates a rumble.

When you taste, smell. see, or even think about food.the glands that line your stomach start making gastricjulce,a mixture of enzymes, water. and acid. The enzyme pepsinstarts the digestion of proteins such as those in milk, meat.and fish. But pepsin cannot work unless it is in an acid.

100

6. How does the stomach acid keep from digestingthe stomach itself? (Glands in the stomach producea special coating that protects it.)

Conclude the discussion. Discuss the concept of hav-ing a pleasant time at meals. Ask your student what hecould do to help make mealtimes pleasant at home.(Answers will vary. Among them might be thefollowing:getting to the table when he is called, eating everythingthat is on his plate, and thanking Mother for the meal.i(BAT: 6c Spirit-filled) Display the digestive tract onpage 18 of the Home Teacher Packet and point out thelocations of the three parts that your student has studied.

117

The acid the stomach makes is hydrochloric acid.Besides making pepsin work. it kills some bacteria that youoften swallow with food.

You may wonder what keep> the stomach acid fromdigesting the stomach itself. Many glands in the stomachproduce it special coating that protects it. If too littlecoating is produced or if 100 much acid is produced. theacid can eat into the wall 01 the stomach. The pit or holethat is eaten out is called an ulcer. Worry and lear cancause the brain 10 tell the stomach to make more acid thanis really needed, Why should vou tr) to haw" pleasanttime ill meals?..Beller is a dinner (~rherbs where love is. than a stalled ox(11/(] hatred therewith." Proverbs 15:17

101

Evaluating the LessonConduct an oral evaluation. Instruct your student tolisten carefully as you read a number of statements. Askhim to tell you if the statement is true or false. If thestatement is false, ask him to explain why, backing uphis explanation with specific information from his text.

1. A person's stomach is just below his waist. (False)2. The stomach has muscles that work like the mus-

cles in the esophagus. (True)3. The muscles make the food whirl around as an egg

beater would. (False)4. The muscles squeeze in on the food in the stomach.

(True)5. A person's stomach growls only when it is empty.

(False)6. Both the stomach and the mouth work on food in

two ways. (True)7. The hydrochloric acid in the stomach kills bacteria.

(True)8. The acid can eat a hole in the lining of the stomach.

(True)9. A hole in the lining of the stomach is called a

pepsin. (False)10. Glands in the stomach start making saliva when a

person smells or sees food. (False)

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For Your InformationThere is something to the saying "It's all in your

mind" when a mother tries to convince her child in theback seat of the car that he is not really that sick to hisstomach. The process of vomiting is controlled by themedulla of the brain, not by the stomach. As the childfeels more and more nauseated, his brain signals thepyloric valve between the intestine and the stomach torelax. At the same time, the diaphragm muscle and theabdominal muscles contract, pushing the partially di-gested food to the upper part of the stomach near theesophagus. The brain signal to the sphincter makes itrelax also, and the muscles of the abdomen continue toforce the food upward so that it can be expelled byvomiting.

SCIENCE 4 HTE

Lesson 27The Intestines

Text, pages 102-6

Preview LessonObjective Introducing the Lesson

Complete the model of the digestive system. Withoutcommenting about the parts or their functions, allowyour student to help you set up the rest of the model.Beside the blender jar representing the stomach, placethe small dishpan and put the fluffy hand towel into thedishpan. In front of that dishpan, set two quart bottles,without labels. Set the pail beside the dishpan, and putthe sponge into the pail. Use the flexible straws to con-nect the containers as shown in Figure 27-1.

Ask your student to tell what he thinks these addi-tional items represent in the digestive system. Allowtime for his ideas. Then tell him that he will find out inhis reading today what part each item represents.


• Explain the function of one part of the digestivesystem.


• The model of the digestive system used in Lesson 26.• I small dishpan.• 1 fluffy hand towel.• I pail.• I sponge.• 2 quart bottles.• 2 labels.• 1 felt-tip pen.• 6 flexible straws.• I paper towel.• I tablespoon of table salt.• 1 tablespoon of sugar.• 1 package of unsweetened Kool-Aid. *• 1 tablespoon of lemon juice.• Home Teacher Packet, pp. 20-21.

Figure 27-1

quart bottles


The IntestinesLittle by little the food that is now liquid leaves the

bottom of the stomach through a valve called the pyloric

sphincter. Pyloric comes from two Greek words that mean"gale watcher." What do you think the pyloric sphincterdoes? Regularly, the "gate watcher" opens and a spoonfulof liquid food, or chyme, moves on to the next stage ofdigestion.

The small intestine is about twenty-three feet long, butit is narrow, only about an inch and a half across at thewidest point. It has two layers of muscles that worktogether in peristalsis, keeping the chyme moving.

The intestine is lined on the inside with microscopicprojections called villi, which look something like thestrands on a shag rug. 1n fact, the inside of the intestineresembles deep-pile carpeting. How many villi do you thinkyour small intestine has? It has about five million.

102

Teaching the LessonDirect a text activity on pages 102-6. Use the follow-ing questions to initiate your student's interest in whathe is going to read.

1, What do the dishpan, the towel, and the bottlesrepresent?

2. What is insulin?Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read,

The model of the digestive system isreferred to in several questions. Youwill want to have it available for yourchild to see during this discussion.

1. What part of the digestive system does the dishpanrepresent? (the small intestine)

2. How long is the small intestine? (about 23 feetlong) It is as long as approximately seven childrenyour student's age lying head to foot across thefloor. Since the intestine is so long, how does it fitinto a small space? (It is bent and twisted andcoiled in the abdomen, You might compare it tothe path in a maze.)

120

The villi have cells that absorb nutrients from the chymeas it passes through the intestine. Blood vessels in the villipick up the nul ricnts. The food you ate earlier is now a partof the bloodstream.

Two glands near the small intestine put out substancesthat cause food to continue breaking down. The pancreasmakes three enzymes that act on starches, proteins, andfats. It also produces insulin. Insulin makes the body's cellsable to use the sugar that is absorbed into the bloodstream.

If there is not enough insulin in the bloodstream, adisease called diabetes mellitus results. How docs diabetesmellitus interfere with digestion? People with diabetes caneat special foods and take insulin SQ that they can keep theright amount of sugar in their blood.

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3. What does the towel in the dishpan represent? (vil-li) Run your hands lightly across the little strandsof the towel. The villi along the walls of the intes-tine are somewhat like those strands, What is thepurpose of the villi? (The chyme or liquid foodruns along all the surfaces of all those villi, andthe millions of cells on those surfaces soak up thenutrients. The cells pass the nutrients into thebloodstream, )

4. What does the first bottle represent? (pancreas)What does the pancreas make? (three kinds of en-zymes and insulin) Give your student the label forthis bottle, Allow him to write pancreas and belowthat, in parentheses, enzymes and insulin.

5. What is the purpose of the insulin? (Insulin makesthe body's cells able to use the sugar that is ab-sorbed into the bloodstream,)

If your child is familiar with diabeteshe may be interested in doing someadditional study on the disease, but atthis point, it will be sufficient for himto understand that when there is notenough insulin in the bloodstream, thebody's cells cannot use the sugar thatthey absorb,

SCIENCE 4 HTE

The liver also works on poisons that get into thebloodstream. It neutralizes poisons or makes thcmharmless. Drugs and alcohol arc poisons. If the liver has todeal with too much poison. it becomes diseased. Then it isunable to perform many of its important jobs.

The liver is a big gland that has SOO different functionsthat we know of. One thing it docs is produce bile. a greenliquid that help> break down fats. Bile works on fats muchlike dish-washing detergent works on grease. Do oil andwater mix very well" How does detergent change the oil?What do you think bile does to fats? Bile also helps thebody absorb vitamins.

104

After the chyme passes through the small intestine. itgoes into the iorge intestine. The large intestine absorbswater and salts. Digestion is now complete. Any fiber ormaterial that the body did not digest travels through therest of the large intestine and is eliminated as \\ aste.

Our bodies need vitamins. minerals, proteins, andsugars to operate well and to stay healthy. What you cat isextremely important. All that your body has to work withcomes from the food you choose. Proteins build musclecells; fats provide energy: minerals build bones. teeth. andblood. Sugars prov ide energy. but they are quickly used up:If you eat a variety 01 good foods, vou will probably begiving your body what it needs.

Staying healthy is not the only reason people cat. Eatingis also enjoyable. The fuur main tastes combine intothousands of delightful sensations for your mouth. Andpeople enjoy being together when they eat. enjoying oneanother's company. In fact. the word companion. meaning"friend," comes from Latin words that mean "to take breadtogether.""Neither have I gone bockfrom the commandment ofhislips: f huve esteemed the words of his mouth more than mynecessarvfood, " Job 23: 12

105

6. What does the second bottle in the digestive systemmodel represent? (liver) What does the liver do?(It neutralizes poisons in the body.) What is onething that the liver produces? (bile)

You rriay want to take this opportunityto talk with your child about the dan-gers of drugs and alcohol, not only tothe body, but also to the mind. Em-phasize that anything that destroys thebody, which for the Christian is thetemple of the Holy Spirit, or turns themind from seeking after God is wrongand should be rejected. (BATs: 1c Sep-aration from the world; 3b Mind; 3dBody as a temple)

Conclude the discussion. Display page 21 of the HomeTeacher Packet. Show your student the amount of timefood takes to go through each part of the digestive tract.Allow him to tell what each part does to the food as thefood passes through the digestive tract.

7, What does the pail represent? (the large intestine)What does the sponge inside the pail represent?(the absorption of water and salts)


About TasteI. Get a clean, dry towel. some salt, some lemon juice.

some sugar, and a package of unsweetened Keel-Aid.

2. Dry off your tongue with the towel.

3. Let your teacher put some sugar on your tongue. Canyou taste it'!

4. Now let saliva cover your tongue, Do you taste thesugar now?

5. Let your teacher put some lemon juice on the tip ofyour tongue. Can you taste it'! Try the other foods ondifferent places on your tongue. Can you find the tasteareas on your tongue?


106

Evaluating the LessonGather the materials for a Finding Out activity onpage 106. Lay the paper towel, salt, lemon juice, sugar,and package of unsweetened Kool-Aid on a table. Tellyour student to turn to page 106 in his textbook and toread the steps of the activity.Conduct the activity. Give your student a paper towel.Ask him to dry off his tongue with the paper towel;then sprinkle some sugar on the tip of his tongue. Askhim to indicate by shaking his head whether he can tastethe sugar while his tongue is dry. Instruct him to closehis mouth and let saliva cover his tongue, and then totell you when he can taste the sugar. (As soon as thesaliva covers his tongue, he should be able to taste thesugar.) Point out that only when the saliva moistenedthe tongue could he taste the sweetness of the sugar.Ask him to identify the part of his tongue where hetasted the sugar. (on the tip of the tongue) If he cannotisolate the part of the tongue, allow him to try the testagain.

Ask him to dry off his tongue with the paper towel;then drop a small drop of lemon juice onto the tip ofhis tongue. Instruct him to let saliva cover his tongue,and then to tell you when and where he can taste thelemon juice. (As soon as the saliva covers his tongueand moves the lemon juice to the sides of his tongue,he should be able to taste it.)

122

Test the Kool-Aid and the salt by placing each oneon your student's tongue and questioning him aboutwhen and where he first senses the salt taste or the bittertaste. (The Kool-Aid should not be tasted until it reachesthe back of the tongue, where the bitter taste is sensed.)Conclude the activity. Display the tongue on page 20of the Home Teacher Packet, its sections unlabeled. Askyour student to write the name of the food he tasted onthe section of the tongue where he tasted it. Ask him toturn to page 94 in his textbook and compare the diagramof the tongue on that page with the results of the dem-onstration as recorded on the visual.

For Your InformationThe small intestine has three parts. The duodenum

[doo-a-de' nom], the first 8 to 10 inches of the intestine,mixes food from the stomach with secretions from theliver and the pancreas. The jejunum [jo-joo' nom] is themain site for the homogenization and mixing of intes-tinal contents. Also, nutrients such as sugars, aminoacids, and fats are absorbed along the jejunum. In theileum [Il' e-om] vitamin B12, bile acids, and the remain-ing amino acids and fats are absorbed. Together, thejejunum and the ileum make up 21 to 27 feet of thesmall intestine, and both parts are responsible for ab-sorption of water and electrolytes.

Digestion is completed in the large intestine, a five-foot-long tube with a diameter of about two and one-half inches. The large intestine is located in the abdo-men, in an upside-down, U-shaped curve.

SCIENCE 4 HTE

CHAPTER

7The Moon's Struc-ture and Motions

~

Lessons 28-31

The Moon'sStructure andMotions

107

This chapter discusses the moon's surface, size, mo-tions, and phases. Besides making moon mountains fromplay dough, computing the weights of objects on the moon,and comparing the sizes of the earth and the moon, yourstudent will participate in a Finding Out activity to dem-onstrate the effects of inertia and gravity as those forceshold the moon in orbit.



* 1 apple (Lessons 28 and 29)* Chicken wire (2' x 2') (Family Time 29)* 2 pounds of plaster of Paris (Family Time 29)* 2 pounds of lime (Family Time 29)* Half dozen marbles and small, hard balls of various

sizes (Family Time 29)* 1 bicycle air pump or rubber tube (Family Time 29)* Shellac (optional) (Family Time 29)* 1 globe, 12 to 16 inches in diameter] (Lesson 29)* 1 pear (Lesson 29)* 1 strip of wrapping paper (2' x 6") (Lesson 30)

123

FamilyTime 28Making Play

Dough

You will need to have a batch of playdough ready for Lesson 28.

Instructions

Materials

Prepare one batch of play dough using the followingrecipe or one of your choosing. Combine all the in-gredients in a saucepan and cook over low heat for aboutthree minutes, stirring frequently. When the mixtureforms a ball, remove from heat. Add food coloring, ifdesired. After the mixture has cooled, store in an airtightcontainer. Do not refrigerate. This mixture will keep amonth or more.You may choose this alternate recipe. Mix together1 cup salt, 2 + cups flour, 1 tablespoon cooking oil, and1 cup water.

Have available:• 2 cups flour.• 1 cup salt.• 2 cups water.• 4 teaspoons cream of tartar.• 2 tablespoons cooking oil.• Food coloring (optional).

124 SCIENCE 4 HTE

Lesson 28The Moon'sFeatures


Preview LessonIntroducing the Lesson

Direct a demonstration. Ask your student ifhe remem-bers the three layers of the earth. (NOTE: In SCIENCE 2for Christian Schools, Home Teacher's Edition yourstudent made a model of the earth's layers using threecolors of play dough. The book also used an apple asan illustration of the earth's layers.) Show page 22 ofthe Home Teacher Packet. Tell him that you will usean apple to illustrate. Cut the apple in half and ask himwhat the peel represents. (crust) What would the whitepart under the skin of the apple be? (mantle) Whatwould the core of the apple represent? (core)

Direct an investigation. Give your student a portion ofplay dough or modeling clay. Instruct him to form veryjagged mountains; then ask how he thinks the mountainson the moon differ from the mountains on the earth.Ask whether wind would change the mountains on earthand how that would happen. (by blowing sand and grav-el and smoothing some of the jagged places) Ask wheth-er water changes the mountains on earth. (yes) How?(by eroding the soil and rock in places) Ask him whathe would expect if the moon had no water or wind. (Nosmoothing or eroding would take place.)

Tell your student to place his mountain in a pie panand pour water over it. Ask whether the water smoothsout the mountain. Tell him that water causes erosion onthe earth, but such erosion would not be present on themoon because there is no water there.


do the following:• Identify the four features of the moon's surface:

plains, mountains, craters, and rills.• Describe why the mountains of the moon are morejagged than those on earth.


• 1 apple.*• 1 pie pan.• Play dough or modeling clay, prepared in Family

Time 28.• Home Teacher Packet, p. 22.


The Structure of the MoonHave you ever looked for "the man in the moon"? Some

people think the dark places on a full moon look like aface. What do you think those eyes and nose and mouthreally are?

The Surface of the MoonA long ti me ago, people thought that the moon had

continents and oceans much like the earth has. Theyassumed that the dark places on the surface were waterThey named the dark spots maria. meaning lunar "seas."We know now that these are not seas at ale but large plainsshaped much like circles. There are about thirty maria onthe side of the moon facing us. The one in the middle iscalled Mare Imbrium. It is about 1.100 km (700 mi) across.

108

Teaching the LessonDirect a text activity on pages 108-11. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. What are four features of the moon?2. What is the most famous feature of the moon?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. How did people a long time ago think that the

moon and the earth were alike? (They thought bothhad continents and oceans.)

2. Why were the dark places named maria? (Peoplethought they were seas or water.) What are thedark places? (Large plains shaped much like cir-cles.) (NOTE: [Latin] maria [ma're-oj-seas; mare[ma'raj -one sea)

126

Besides the flat regions, the moon also mouma.nsand mountain ranges, named like mountains on earth,There are more mountains in the southern hemisphere of

the moon than in the northern hemisphere. Some of themountains are more than 7,500 meters (25.000 ft) highalmost five miles high' How do you mountains onthe moon differ from the mountains on earth') How dowind and water change the mountains'! How do themountains on the moon look? \Vhy?

Probably the most famous features of moon are itsmany craters. 'The word crater comes from the Greek wordfor "cup" or "bowl-shaped." How a crater like a cup abow]'! Some craters have light streaks called rays thatspread out all directions. One crater with such rays iscalled Tycho. During a full moon these rays look like thetop of a peeled orange.

109

You may wish to share the followinginteresting information with yourchild. In 1610, an Italian scientistnamed Galileo aimed a telescope (oneof the first ever built), or "optic tube, "as he called it, at the moon. Instead ofbeing a round object that has light anddark areas, the moon was a place thathas mountains and lowlands, rough ar-eas, and smooth areas. When Galileolooked through his telescope, he sawthat the dark areas were smoother andappeared to be lower than the lighterareas, which were higher and morerugged. Galileo thought that the darkareas might be oceans; so he namedthem maria, which is the Latin wordfor "seas."

3. Where are most of the mountains located? (in theSouthern Hemisphere)

4. What is the most famous feature of the moon?(craters) What does the word crater mean? (cupor bowl-shaped)

SCIENCE 4 HTE

Many other crater> are surrounded by steep "ails thatrise high above the moon's surface. some as much a, 6,000meter" (20,000 ft.) above the bottom of the crater. Themoon's craters look somewhat like the crater; on earth thatwere formed by volcanoes.

Observers have counted at least 30,000 craters on themoon. Some areas have so manv craters that they overlap.Craters range in size from a, small as a soup bowl to solarge that it would take ten hours at sixty miles an hour todrive around the rim. Bailley is the moon's largest crater.being 295 km (183 mi) across.

Scientists think that most of the moon's crater. wereformed when meteors hit its surface. They collided with themoon at great speeds and exploded. The great explosionscaused craters much bigger than the meteors themselves.

110

5. Look at the picture of Tycho on page 109. Whatare the light streaks that spread out in all directionscalled? (rays)

6. How many craters have been counted on themoon? (30,000) Some scientists have estimatedthat there are 200,000 craters on the moon.

7. What size are the craters? (They vary-from the sizeof a soup bowl to about 200 miles across.) Do allthe craters look the same? (No, some are evenstacked on top of each other.)

8. How are craters formed? (by meteorites strikingthe surface, by the collapse of the top of a volcano,by the violent eruption of lava from a volcano)

9. Name the fourth feature of the moon. (rills) Whatare rills? (cracks or canyonlike valleys) What sizeare the rills? (from a few feet to three miles wide;some are hundreds of miles long) What causes therills? (moonquakes, perhaps) Instruments left onthe moon's surface have recorded about 3,000moonquakes per year.


Some craters may have formed like volcanic cratersform on the earth. Gases from the interior of the moonescape through cracks in the moon's surface. The gases thenexpand because there is no atmosphere to keep themcontained. The expanding gases tear away the moon'ssurface material, causing craters.

A fourth feature of the moon is the cracks. called rills.These canyonlike valleys that run along the lunar surfacemay be straight or curved. They arc from a few feet to threemile, wide, and some are hundreds of miles long. Mostscientists believe rnoonquakcs caused the rills. What do yousuppose a moonquakc is like?

'.J ')

.-I'

/',I

ts.

I

1) .Conclude the discussion. Ask your student to name thefour features of the moon. (plains, mountains, craters,and rills)

111

127

name _

The Moon's FeaturesClrele the corrtet Ioc.llon of thl.1 "••••."

/Lebel the I.yerl of the moon.

earth ~ ~ moon

In each box below, write the nem. of e.ch I•• ture.

crater plain

CI990 Bob Jones Univlt,sity Press, Roproduction prohibited

D Sdence4Notebook Pad<et

lesson 28EvatuatingtneLeuon

Evaluating the LessonDirect a notebook activity on page 31. Tell your stu-dent to follow the directions on the page. When he hascompleted the page, discuss the answers and make surethat he understands the main features of the moon.

For Your InformationAccording to a German folktale, "the man in the

moon" was a stealer of cabbages who was put on themoon for punishment as an example to anyone whomight think such an activity profitable. In Greek andRumanian folklore, he is not a man at all, but a woman,the sun's sister, the Lady of the Night. To some people,the dark parts seem to form a rabbit. Still other peoplehave said that the dark parts of the moon seem to formtwo people.

Although the moon is our planet's only natural sat-ellite, it is not the only natural satellite in our solarsystem. There are more than 40 known moons. Ourmoon is not the largest either. Of the 16 moons thatorbit Jupiter, three are larger than our moon. Whatmakes our moon unique is its size in relation to itsplanet. It is nearly one quarter the size of the earth-proportionally much larger than any other moon in oursolar system.

128

31

Some of man's early beliefs about the moon seemquite comical now. For instance, in the seventeenth cen-tury Sir Paul Neal announced that he had seen an ele-phant on the moon. He later discovered that the "ele-phant" was in reality a mouse that had managed to getinside his telescope.

A great stir was created by a man named RichardLocke when, beginning on August 21, 1835, he begana series of articles about the moon. While there was notruth to the claims these articles made, many peopleincluding scientists believed every word. Locke wroteabout the "discoveries" made by a then famous astron-omer, Sir John Herschel. Locke claimed that throughthe use of a very strong telescope the astronomer hadseen fabulous mountains made from precious jewels andmany odd creatures, including apelike men with bats'wings. A year later these articles proved to be a hoax.

SCIENCE 4 HTE

Figure 29-1

FamilyTime 29Model of the

Moon's SurfaceIf time permits during this chapter, youmay want to work with your child tobuild a model of the moon's surfaceusing the following directions.

2


• A large salad or mixing bowl with completely round-ed bottom, at least 15 inches in diameter.

• Chicken wire (2' x 2').*• 1 flat pan for mixing.• 2 pounds of plaster of Paris.*• 2 pounds of lime.*• Strips of cloth to cover completely the surface of thebowl.

• 6 marbles and small, hard balls of various sizes.*• 1 bicycle air pump or rubber tube.*• Shellac (optional).*

3

4

InstructionsGuide your child with the following steps. You willwant to refer to Figure 29-1.1. Invert bowl and shape chicken wire around it. You

will need several hands to hold it down.2. Prepare a very diluted mixture of plaster of Paris,

lime, and water in the flat pan. Soak the cloth stripsin the mixture and lay them over the chicken wireso that the strips completely cover the wire. Thestrips will form a wet base to hold the plaster ofParis.

3. Pour three parts plaster of Paris and two parts limeinto the pan. Add water and mix into a smooth,easy flowing mixture. Then slowly pour over thetop of the covered wire to form the surface of themoon.

4. Immediately, toss small balls and marbles at thewet surface. (The craters represent those made bymeteorites striking the surface of the moon.)

5. Insert the end of the air pump or rubber tube underand through the chicken wire, between the clothstrips, and halfway through the plaster of Paris.Then force air through. Repeat as many times as

5

6

possible. (The results represent volcanoes formedby internal pressure.)

6. Remove the marbles and balls from the "moon's"surface, and allow it to harden overnight. You maywant to cover the model with a coat of shellac.

For special effect photographs, place the model in adarkened room, point a flashlight at the surface, andtake time exposure photographs. Move the flashlight toanother position and note the' 'lunar" shadows.

Chapter 7: Family Time 29 129

Lesson 29Description of

the MoonText, pages 112-16


PreviewObjectives


• Compute what the weight of various items would beon the moon.

• Label the perigee and apogee of the moon's orbitaround the earth.


• A Write It flip chart.• 1 globe, 12 to 16 inches in diameter.*t• I rubber ball, about one-quarter the size of the globe.• Ball of string.• Strip of adhesive tape.• 1 bathroom scale.• I pear.*• I apple.*• Home Teacher Packet, p. 23.

Prepare:• A diagram of the orbit of the moon by tracing thediagram in the upper box on notebook page 33 ontoa page of the Write It flip chart. (NOTE: Do notinclude the terms perigee and apogee.)


Direct a demonstration. Ask your student how muchsmaller he thinks the moon is than the earth. (Answerswill vary.) Display page 23 of the Home Teacher Packetto show the size relationship between the United Statesand the moon. Tell him that if the earth were the sizeof a basketball, the moon would be no bigger than abaseball. Compare the size of the globe and the' 'moon"ball.

130

The moon seems as big as our sun, but the moon is400 times smaller and 400 times closer. To get an ideaof how close the moon is, ask your student to imaginethat the whole solar system has been shrunk. In the smallscale, the distance from the earth to the sun would be100 feet. On this scale, ask him to guess how far fromthe earth the moon would be. (3 inches) Ask him towind the string around the equator of the globe ten timesand cut it at this point. Tell him to remove the stringfrom around the globe and attach one end to the"moon" ball with adhesive tape. Allow him to tape theother end of the string to the globe at any point on theearth's equator and stretch the string its full distance.Tell him that he has just constructed a scale-model ofthe earth-moon distance relationship.

--- Teaching the LessonDirect a text activity on pages 112-16. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. What is mass?2. How much would you weigh on the moon?3. Is the temperature on the moon higher or lower

than on the earth?

SCIENCE 4 HTE

The Gravity of the MoonAlthough the mass of an

object does not change indifferent places, its weightHow can this be'> Weight dependson gravity, but mass does not.The more pull of gravity there ison an object the more the objectwill weigh. Do you think youwould weigh the same on themoon as on the earth?

Your mass the same on themoon and the earth) but yourweight is different. The gravity onthe moon is about one-sixth 01that on earth. This means thatyou weigh sixty-six pounds onearth, you would weigh elevenpounds on the moon

How would the gravity on themoon change your abilir, to playsports'> 1\ high Jumper who canjump six-and-a-half feet on earthcould jump thirty-nine feet highon tbe moon. Imagine being ableto jump up to look into a third-story wind owl ynu can hit abaseball 400 teet on earth. youcould hi! the same ball almost a

113

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.L How much smaller is the moon than the earth?

(about one-fourth the earth's diameter)2, What is mass? (how much matter something has)

Think of two blocks that are exactly the same size,one of metal and one of plastic. Which one wouldcontain more mass? (metal) When we ask someonehow much he weighs, we are really asking aboutmass, or how much matter is contained in his body,

3, Is your mass the same on earth as it would be onthe moon? (yes) Is your weight the same on earthas it would be on the moon? (No, you weigh lesson the moon.)

Mass should not be confused withweight, Mass is the measure of howmuch matter an object has. Any objectwill have the same mass in any gravi-tational field. Weight, the measure ofhow much gravity pulls on an object,varies from place to place,


The Shape of the MoonAlthough the earth and the moon are both bail-shaped.

neither is perjectty round. The slower an object spinsmore nearly round it is. A planet that spins fast will beslightly wider around the equator. The earth aroundonce in twenty-four hours. The moon spins around onceabout twenty-eight days, Which body faster" Which ismore nearly round the earth or the 11100n')

The Distance of the Moon from the EarthThe path the moon takes around the earth is not

perfectly round. What the path called? It is 311 ellipse.Look at the diagram of (he positions of the moon. Is the

moon the same distance from the earth in A it IS in B?Because this distance changes the moon goes around theearth. we talk about the moon's average distance from theearth. 1 his distance is halfway between closest andfarthest points from the earth.

Moon's elliptical orbit

114

4, What does your weight depend on? (gravity)5, How much would a six-pound object weigh on

earth? (six pounds) How much would the sameobject weigh on the moon? (one pound, or one-sixth as much as on earth)

6. Do you remember what shape the people in Col-umbus's day thought the earth was? (flat) Isaiah40:22 (written some 700 years before Christ) de-clares that the earth is a circle (i.e, sphere).

7, Which spins faster, the earth or the moon? (theearth) Which body is more nearly round? (themoon)

8. How long does it takes the moon to orbit the earth?(29+ days) How long would a person be in lightif he stayed in the same place on the moon for amonth? (14+ days)

131

The average distance between the moon ane! the earth is385,000 krn (2)9.000 mil, To travel this distance on earthyou would have 10 go around the earth more than nine-and-a-half times, if you would show every mile from here

10 the moon a, one inch, how many inches away would youplace the moon on this scale?

You would need enough inches to equal almost fourmiles!

The Moon's TemperaturesDo you think the moon is colder or warmer than the

earth? If you guessed colder, you are right. BUI youguessed warmer you are also right. There are greatervariations in surface temperatures on the moon than therearc on earth, Why is this so? What causes temperatures onearth to vary less than the temperatures on the moon? Ouratmosphere acts a~ an insulator to keep temperatures aboutthe same

115

9. How high is the daytime temperature on the moon?(260 OF) How low is the nighttime temperature onthe moon? (-280 OF) What accounts for the varietyin temperatures? (Unlike the earth, the moon hasno atmosphere to enable it to trap heat.) Look atthe cartoon on page 116.

10. What is the changing temperature called? (surfacetemperature) What is the temperature of the corecalled? (stable temperature)

11. Look at the picture on page 114. What is the shapeof the moon's path around the earth? (ellipse)

12. What is the average distance from the earth to themoon? (239,000 miles) How many trips would aperson have to take around the earth to travel thatdistance? (9+)

Conclude the discussion. Display the prepared diagramon the Write It flip chart. Ask your student what thediagram pictures. (the moon's orbit) Tell him that thepoint in the moon's path where it is closest to the earthis called perigee. At perigee the moon is 221,000 milesfrom the earth. Write the term perigee on the appropriateline on the diagram. The point where the moon is far-thest from the earth, the apogee, is 253,000 miles away.Add this term to the flip chart diagram. To demonstratethese names and make them easier to remember, hold apear close to your body and an apple at arm's length.

132

The moon orbits the earth completely about once every29 Y, days. If you could Slay in the Same place on the moonfor a month, you would in light for half of that time (14% days).

During a moon day the temperature may reach 2600 EThe night, though, may bring temperatures as low as,280cF, Without all atmosphere like the earth's, the moon isunable to trap heal, As soon as one side turns away fromthe sun, it immediately cools off. This changingtemperature is called sur/lice temperature. The moon alsohas stable temperature, the temperature of its core,

116

SCIENCE 4 HTE

name _

How Much Would ItWeigh?For etch obfec:t, compute Ita weight on the moon.

~

~earth: 12,000pounds

moon: 2,000Ib,

earth: 84 pounds earth: 12 pounds

141b,moon:

earth: 6 pounds earth: 2,400 pounds

moon: 400 Ib,

earth: 180 pounds

moon: 301b,moon: 11b,

YOU

earth: 300,000 pounds

moon: 50,000Ib,

earth: 1,200pounds earth: _

2001b, moon: _moon:

'1U90 Sob Jone, Univerilly Prell,ReprO<!uc!lon prohibited.

D'Sdence4NoIebook' ••••

Leuon2aEvalu.llnglfl.L ••• on

Evaluating the LessonDirect a notebook activity on pages 32-33. Instructyour student to follow the directions to complete theevaluation, You may find it helpful to work the first twoboxes together. Tell him to draw a picture of himself inthe last box on the page,

For Your InformationMan wondered for centuries at stories of strange

creatures and wild terrain on the moon, Until the begin-ning of unmanned space travel in 1964, he had to relyon telescopes to give him the information he craved,Many large features could be seen on the near side ofthe moon, but nothing was known about its mysteriousfar side,

During 1964 and 1965, seven Ranger spacecraftwere launched for the purpose of photographing themoon's surface. Five of these were successful, sendingback thousands of photos before each crash-landed onthe moon. Then followed the five Lunar Orbiters, whichsuccessfully charted almost the entire hidden side of themoon.


32

name _

Fill In the correct word •.

Moon's orbit

Today's high on the moon

willbe~oE

Tonight's low will be-280 0 E

Mass or WeightI need to lose

some mass

C>1990BobJones UniversltyPress. Reproduction prohibited.

QSdence4U Notebook Packett.eooon2eEvaluaUng !he lnIon

On July 2, 1966, Surveyor I made the first controlledsoft landing on the moon. It sent more than ten thousandpictures back to the earth. Between this landing andJanuary of 1968, four more Surveyors successfully land-ed on the moon.

On July 20, 1969, the first manned spacecraft landedon the moon. Vast desolation greeted Neil Armstrongand Edwin Aldrin, Jr. The moon's lack of atmosphereand water meant that there were no storms, clouds, orweather of any kind. There was no sound, since soundwaves need atmosphere to be transmitted. They foundno life on the moon, not even the hostile germs andbacteria that scientists feared they would find.

133

Lesson 30The Moon'sMotions


PreviewObjectives


• Identify the rotation-revolution pattern of the moon.• Demonstrate the effects of gravity and inertia.


• I dictionary.t• 1 strip of wrapping paper (2' x 6").*• 1 book.• 1 rope, 4 feet long.• 1 large stuffed animal.


Introduce a Finding Out activity on page 118 andnotebook page 34. Tell your student that the force ofgravity helps to keep the moon in its proper path. Askhim why the moon does not crash into the earth. Tellhim that in his activity today he will learn about anotherforce acting on the moon. Ask him to gather the mate-rials. Instruct him to tie the rope securely around thestuffed animal. Take him to an open area such as theback yard.

134

About Inertia

I. You will need a heavy but soft object (like a largestuffed animal) and a rope.

2. Go outside, Tie the object to a rope about four feetlong. Swing the rope around your head so that theobject goes in a circular path, What would happen tothe object if the rope were cut" In which directionwould the object travel? Let go of the rope. Watch tosee the direction that the object travels.

3, The object flying off represents the force of inertia,What represents the force of gravity"

4. In your notebook, draw diagrams of how the moonmight travel without the forces of gravity and inertia.

118

Direct the activity. Instruct your student to hold theend of the rope and swing the stuffed animal aroundabove his head. Discuss the questions in Step 2 withyour student. Then tell him to let go of the rope and towatch to see the direction that the object takes. Explainthat the object's flying off represents the force of inertia.Inertia is the tendency of an object to stay in one placeor to keep moving in a straight line. Ask him whatmovement represents the force of gravity. (the object'sfalling to the ground)

SCIENCE 4 HTE

name _

nndlng Out About Inertia

Draw diagram. of how the moon might travel without the forces 01 gravity and Inertia.

01990 Bob JOIl •• Unlv.r,lty Pr •••. Reproduction prohlbll~.

O Sdence4' ,NoIIebook , ••••••

"lellon30

T.lehlnllth,L •• lon

Direct the use of notebook page 34. Upon returningindoors, your student should draw a diagram on note-book page 34 showing how the moon might travel with-out the forces of gravity and inertia. Call attention tothe fact that these forces are part of God's marvelousplan. Colossians 1:16-17 says that Christ created allthings and by Him all things consist (or hold together).(Bible Promise: I. God as Master)

Teaching the LessonDirect a text activity on pages 117-19. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. What are the two forces that act on the moon to

keep it in its path?2. In what direction does the moon revolve?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. What is the shape of the moon's path around the

earth? (ellipse)2. What are the two forces that act on the moon to

keep it in its path? (gravity and inertia)


34

3. Find the definition of inertia in the dictionary.("the tendency of a body at rest to remain at restor of a body in motion to stay in motion in astraight line, unless disturbed by an externalforce" )

4. Lay a strip of paper on a table and place a bookon top of it. Can the book move by itself? (no)How can you move it? (push it with his hand; pullit with the paper) What do we call the tendency ofthe book to stay in its place? (inertia) What do wecall the tendency of a bowling ball to keep rollingdown the lane once it is released? (inertia)

5. In what direction does the moon revolve? (coun-terclockwise) In what direction do all the planetsrevolve? (counterclockwise) Why do you thinkGod made all the planets to revolve in the samedirection? (Answers will vary.) (Bible Promise: I.God as Master)

6. How fast does the moon revolve around the earth?(2,200 miles per hour) How long does it take themoon to revolve around the earth? (about onemonth) (NOTE: The word month is derived fromthe word moon, and a month represents a"rnoonth" of time.)

7. The moon also spins around as it revolves. Whatis the spinning motion called? (rotation)

8. How long does it take the moon to make one ro-tation? (one month)

135

Pretend you are looking down onto the earth and themoon from space. In which direction do you think themoon revolves around the earth, clockwise orcounterclockwise? How does this direction compare with

the earth's revolution around the sun') Do you think it isthe same') The moon orbits the earth counterclockwise: theearth orbits the sun in the same direction. The other planetsrevolve around the sun in the same counterclockwisedirection. What can you say about the design of God'suniverse?

The moon revolves around the earth at the speed ofabout 3500 krn (2,200 mil per hour. At this speed themoon travels over one-half mile in one second,

RotationThe moon also spins or turns as it revolves around the

sun, We call this spinning motion its rotation.The moon takes as long to turn around once as it docs

to travel around the earth. How long does the moon take togo completely around the earth once'! Then how long doesit take to rotate once?

Do you think men can ever see the back of the moonfrom earth') Why not"

119

Conclude the discussion. Tell your student that themovement of the moon is similar to the movement of amerry-go-round horse, The same side of the horse al-ways faces the merry-go-round's center, just as the sameside of the moon always faces the center of its orbit-theearth, That is why we see the "face" of the "man inthe moon" and never the back of his' 'head," Ask yourstudent if he thinks anyone has ever seen the back ofthe moon, (Yes, those who have gone to the moon itselfhave seen the back of the moon,and others have seenpictures of the back of the moon.)

136

name _

Circle the correct anlwer.

(0) Rotation~8Does the moon move this way? Yes~

(()-()\ Revolution

()8() Does the moon move this way? Yes <1iV\()-())

(~-~\ Rotation and Revolution

()8f) Does the moon move this way? ~ No

\~-~)

Trace each orbit with a different color.

K"earth's orbit around the sunmoon'sorbitaroundtheeanhmoon's orbit around the sun

01990BobJonesUniversityPres5,Reprot!uctiOTlprohibited

D Science 4Note_ Packet 3S

Evaluating the LessonDirect a notebook activity on page 35. Ask your stu-dent to read the directions at the top of the page, andthen instruct him to complete the page, (NOTE: Yourstudent may find it easier to answer the first two ques-tions if he inserts the word only in each question.)

For Your InformationSand castles are built daily on beaches, only to be

destroyed a few hours later by water that was yardsaway when the castle was built The ocean seems to"come in" to gobble up the castles and then silently"go out" This change in the water's surface level iscalled tides,

Just as the sun's gravity holds the moon and planetsin orbit, the earth's gravity also pulls everything on theearth toward the earth, The moon also pulls the earth;in fact, everything in the universe attracts everythingelse, Some bodies have a greater pull because of theirgreater mass, That is why the earth orbits the sun, andnot the other way around, The sun, planets, and moonsare all pulling toward each other in space, It is themoon's pull on the earth that causes the tides,

SCIENCE 4 HTE

Direct an activity. Discuss the following questions withyour child.1. Why do bicycles have reflectors? (so that people

in a car can see the bicycle and its rider)2. What makes the reflectors light up? (They reflect

the car's lights.) (NOTE: At this time you can shinethe car's lights on the bicycle reflector.)

3. Would the reflectors still reflect the car's lights ifthe bicycle were on the other side of a hill or behinda bush? (no) (NOTE: Ask your child to take hisbicycle behind a bush.) Why not? (The hill or bushwould block out the headlights so that the reflec-tors would not reflect any light.)

4. How is the moon like the reflectors on the bicycle?(Answers will vary.)

FamilyTime 31

Lunar and SolarEclipse

If time permits, use this page to teachthe concept of solar and lunar eclipse.You will find it beneficial to teach thislesson in the evening.

Continue a discussion. Explain to your child that themoon does not have its own light. If it did, people onearth would be able to see the whole moon all the time.The moon can be seen because it reflects the sun's light.Ask him what would happen if something came betweenthe sun and the moon that blocked the sun's light. (An-swers will vary. The moon would have no light to re-flect.) Explain that the moon would be dark and it couldnot be seen. Tell him that sometimes the earth passesbetween the sun and the moon, casting its shadow onthe moon. When this happens, there is an eclipse of themoon, or a lunar eclipse. The people on earth cannotsee the moon.

Ask your child how long he thinks the eclipse willlast. (An eclipse of the moon lasts only about one anda half hours.) Ask him why he thinks the eclipse lastsa short time. (The moon does not stay in one place.)After the moon starts to move out of the earth's shadow,a partial eclipse may be seen. A partial eclipse may lastup to three hours and forty minutes.

Tell your child that there is another kind of eclipsecalled a solar eclipse. Ask him what could possibly getin the way of the sun to cause a solar eclipse. (Answerswill vary.) A solar eclipse occurs when the moon passesbetween the sun and the earth. Ask him whether it seemsincredible that the moon, being so small compared tothe sun, could block out the sun's light. (Answers willvary.) The moon is 400 times smaller and 400 timescloser; so it seems to be the same size as the sun. Tellyour child that he can use a dime held at arm's lengthto block the full moon from view. The dime is muchsmaller but closer; so the two appear to be the samesize. (NOTE: You may want your child to try this dem-onstration.) Ask him whether he thinks there can be asolar eclipse each month. (no, because the moon mustbe in an exact line between the sun and the earth) Tellhim that a total eclipse can last only 3 to 7+ minutesbecause the moon and earth are constantly moving.Only a very small part of the earth's surface is coveredby the moon's shadow. Caution your child that heshould never look at the sun, even during an eclipse.The effect would be very serious.

Notebook, page 36


• 1 dime (optional).• 1 bicycle with a reflector.

InstructionsDirect a discussion. Ask your child if he has seen hisown shadow or shadows formed by other objects. (yes)Ask him what causes a shadow. (Answers will vary.)Explain that a shadow is formed when an object passesin front of a source of light and blocks part of the light.Ask him if he thinks the moon and the earth makeshadows. (Answers will vary.) Tell him that the moonor the earth can pass in front of each other in space andblock out all or some of the light from the sun. This iscalled an eclipse. The word eclipse means "to shutout."

If your child owns a bicycle, you willwant to go outside near the bicycle andthe car.


name _

Label the ph:tu •.••. (Th6ln •• rt jtJetUrt ,haWi whit you would 1M Irom thl •• rth.)

Solar Eclipse

'1990 Bob JOJ'lllS Univerilly P'(lss. Reproduelion prohibited

D Sdence4_racket

Lenon 31

TeacNng the L,"on 36

Direct a notebook activity on page 36. Guide yourchild as he completes the page.

I For Your InformationLunar Eclipse Dates

December 21, 1991 PartialJune 15, 1992 PartialDecember 10, 1992 TotalJune 4, 1993 TotalNovember 29, 1993 TotalMay 25,1994 PartialApril 15, 1995 PartialApril 4, 1996 TotalSeptember 27, 1996 TotalMarch 24, 1997 PartialSeptember 16, 1997 TotalJuly 28, 1999 Partial

Total Solar Eclipse DatesJuly 11, 1991June 30, 1992November 3, 1994October 24, 1995

March 9, 1997February 26, 1998August 11, 1999

138 SCIENCE 4 HTE

Lesson 31The Moon's

PhasesText, pages 120-22Notebook, page 37

Preview LessonObjectives Introducing the Lesson

Direct a demonstration. Place the lamp (without ashade) on a table so that the bulb is at eye level. Turnthe lamp on. Tell your student to stand facing the lamp,about 2 feet from it. Give him the orange and ask himto hold it about 12 inches in front of him. Ask him howmuch of the orange's lit surface he is able to see. (none)

Then instruct your student to turn so that his sidefaces the lamp and to hold the orange in front of him,about 10 inches from his eyes. Ask him how much ofthe orange's lit surface he is able to see this time. (one-half) Instruct him to turn once more, positioning hisback toward the lamp and holding the orange about 10inches from his eyes and slightly to the left of his head.Ask him how much of the orange's lit surface he is ableto see from this position. (all)Direct a discussion. Ask your student how much of thetotal surface of the orange received light in each posi-tion. (one-half) Ask him why he could not see the wholelit surface each time. (Answers will vary.) Tell him thatthe way we see the moon is very much like this. Al-though the sun's light always shines on half of themoon's surface, the whole lit surface is not always seenfrom earth.


• Identify the phases of the moon.• Differentiate between waxing and waning.


• 1 lamp.• 1 orange.• Home Teacher Packet, pp. 24-25.


Teaching the LessonDirect a text activity on pages 120-22. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. What shapes does the moon resemble?2. What causes the different phases?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. What shapes does the moon resemble? (circle, ba-

nana, half circle) What are these different shapesknown as? (phases)

2. What causes the different phases? (the travels ofthe moon in its orbit and the position of the earth)

3. When can the moon best be seen? (at night, earlymorning or evening) Why is the moon not clearlyvisible during the day? (The sun is too bright.)

Display the phases of the moon frompage 24 of the Home Teacher Packet.You will want to give your child timeto cut out the phases and the labelsbefore beginning the next question.

140

Have you ever heard someone speak of the "newmoon"? If then; is such a thing, what happens to the oldmoon? There is rcully one moon. Every time itcompletes one revolution \VC cullit new moon, Youcannot see the new moon because the moon directlybetween the earth and the sun, and its dark side is lacingthe earth.

As moon continues in its orbit a few you canto a little of the moon', lighted Side. It called a

crescent and shaped something like banana, About oneweek alter the moon. you can hall' of the lightedside, This phase is called the first In a lcw moredays you Can almost all of the moon's lighted surfaceseen from earth, At this phase the moon called gibbous,meaning "humpbacked. Docs it look like it hi" aor humped hack to you')ef)()OOOCl(t

When the earth is between the sun and the 111000, thesun shines on the 11100n 's surface so that see all ofus lighted surface. The full moon appears about two weeksafter the new moon. When the muon goes from new moonto full moon the amount of lighted surface we becomes

We say that the moon is waxing, or showing more 01its lighted surface.

What happens to the moon after it passes through thephase of full moon" A few days after the last quarter, themoon becomes a crescent again. Finally, the mooncompletes its journey around earth, and there is amoon once again, What happens to the lighted surface of

moon from Iul! moon to moon'! The moon isIt -aning. meaning that the lighted surface we is gettingsmaller.

121

4. What is the first phase of the moon? (new moon)Why is it called a new moon? (It has completedone revolution.) Can the new moon be seen? (no)(NOTE: At this time allow your student to glue thenew moon phase on the chart with its label. Con-tinue this procedure after each phase is discussed.)

5. What is the meaning of the word waxing? (becom-ing larger, showing more of the lighted surface)

6. What is the name of the stage after the new moon?(crescent) The moon is beginning to show more ofthe lighted surface; so we call it the waxing cres-cent. What is it shaped like? (a banana)

7. What is seen about a week after the new moon?(first quarter or half moon) Why is it called firstquarter since we see half of the lighted surface?(The moon has passed through the first quarter ofits stages.)

8. After a few more days pass by, the amount of thelighted surface increases. What is this phasecalled? (gibbous or waxing gibbous) What doesgibbous mean? (humpbacked)

9. What is the name of the next stage? (full moon)10. What do scientists call the apparent shrinking of

the moon's lighted surface? (waning)11. What is the next phase? (waning gibbous)12. What is the next phase? (last quarter or halfmoon)13. What is the last phase of the moon? (waning

crescent)

SCIENCE 4 HTE

"Then spake Joshua 10 the l.ord ill (he Jar when tlu: Lorddelivered up the Amorites before the children t~llsrae}, andhe said in thr sight of Israel, SUI1, stand thou sill! uponGibeon; and 111011, Moon, in th« valley (J{ Ajalon. And thesun stood still, and tho moon stared, uniii the people hadavenged themselves upon their enemies. " Joshua j(j,</J-J3

122

Conclude the discussion. Direct your student's atten-tion to the picture on page 122. Read Joshua 10:12-14from the Bible. Emphasize the words sun stood still andabout a whole day. Discuss with your student what thatday might have been like. Ask him how he thinks itwould have been different from today. Emphasize thefact that God, through His marvelous power, caused thesun and moon to stand still.


name _

Labellhe phases 01 the moon.

Sun

141

37

waxing crescent waning crescent

Iwfirst quarter or half moon

owaxing gibbous waning gibbous

full moon

C>1990Bob Jones University Press Reproduction prohibited

O Sdenc:e4Note"""" Packet

LeS$Ofl31

EvaJu.tinp the Lenon

Evaluating the LessonDirect a notebook activity on page 37. Instruct yourstudent to label the phases of the moon.

EnrichmentGive your student the Lunar-toon from page 25 of

the Home Teacher Packet. You may want to displayyour student's original cartoon.

CHAPTER

8Animal Defenses

~

Lessons 32-34

~ Animal Defenses

123


This chapter presents the various ways in which Godhas equipped animals for survival. The first two lessonsintroduce the equipment for protecting, or built-in defens-es, such as mimicry, weapons, and camouflage. The lastlesson introduces the actions of defense, known as tactics.A Finding Out activity is included in the first lesson to aidyour student in understanding the concept of camouflage.

143

Lesson 32Camouflage


PreviewObjectives


• Match mimics with the animals they imitate.• Match camouflaged animals with their surroundings.• Name animals whose bright colors signal danger.


• 1 sheet of red construction paper.• 1 sheet of blue construction paper.• 1 sheet of green construction paper.• 1 hole puncher.• 1 stopwatch] or watch with a second hand.• Scissors.• 1 plastic margarine container.• 1 felt-tip pen.• Home Teacher Packet, p. 26.


Gather materials for a Finding Out activity on text-book page 127. Instruct your student to place the sheetsof construction paper, the hole puncher, the stopwatch,the pair of scissors, and the plastic margarine containerin front of him. Give him time to cut the three piecesof construction paper in half horizontally and use thehole puncher to punch many holes in one piece of eachcolor paper, putting the circles into the margarinecontainer.Direct the activity. Allow your student to mix the con-fetti. Place the red half sheet of construction paper inthe center of the table and sprinkle a handful of theconfetti over the sheet. Using the stopwatch, give himfive seconds to count the number of red circles he cansee. Then, using another handful of confetti and the redpaper, let him count the number of blue circles he finds.Continue the activity, using the green and blue halfsheets of paper. Allow him to record his findings on theWrite It flip chart.

144

About Camouflage

I. Get one sheet of red construction paper, one blue sheet,one green sheet, a hole puncher, a slop watch, a pair ofscissors. and a plastic margarine container.

2. Cut the pieces of construction paper in halfhorizontally. Lay one half of each color on a table oron the floor. Punch holes from the other half sheetsand collect them in the container.

3. Stir the confetti So that all the colors are mixed well.Then sprinkle a handful over the red sheet.

4. Giving yourself five seconds, count as many red dots asyou can. Gather the confetti. sprinkle out anotherhandful, and count as many blue dots as you can in fiveseconds. Repeat with the other colors. Record yourfindings.

127

Discuss the results. Compare and contrast the infor-mation obtained in the activity. Ask your student to tellwhy he thinks it was easier to count the circles thesecond time in each case. Elicit the idea that when anobject has the same color as its surroundings, it is muchmore difficult to find.

SCIENCE 4 HTE

"But l wil! sing of' thy power; yea, / will sing aloud 0/ thymen)' in the ntorning.for thou hast been my defence andrefuge in the day a/my trouble." Psa11l159:16

In the days of jousts and crusades, knights buckled ontheir armor and, astride great war horses, rode into battleto defend their land. their honor, and their king.

Ever) day. on a smaller scale, jousts and battles of asort go on in the anima! kingdom. Rhinos in their armor,porcupines with their spear-sharp spines, and caribou withtheir antlers hard as lance; ward off enemies. defend theiryoung, and protect their territories. 1 he clank and crash ofcombat may resound through the wilderness when two big-horn sheep slam together head-on, or it can be as subtleand quiet as a snail pulling into its shell. But everyconfrontation is serious business. often a maucr of life anddeath.

124

Teaching the LessonDirect a text activity on pages 124-26 and 128. Usethe following questions to initiate your student's interestin what he is going to read.

1. What are the defense actions of animals called?2. Find three defenses that God has given some

animals.Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Where can jousts and battles be seen today? (in the

animal kingdom)2. What are the defense actions of animals called?

(tactics)3. Look at the picture of the butterflies on page 125.

What defense does the viceroy butterfly use? (mim-icry) Do these two butterflies look similar to you?(yes)

4. Another mimic is the hoverfly. Can you guess howit mimics the bee? (These flies not only look likebees but also make a buzzing sound when they fly.)Another kind of fly mimics a wasp by imitating thewasp's flight pattern and even bending its abdomenaround and jabbing with it, pretending to sting itsenemy!


Built-in DefensesGod designed each animal with the equipment and

behavior it needs for survival. The equipment forprotecting, or built-in defenses. includes special colors orshapes, weapons, and protective coverings. Animals dodifferent things to defend themselves. These action; ofdefense arc known as tactics.

Special Colors or ShapesThese butterflies are hard to tell apart at first or even

second glance. The appearance of thc viceroy mimics. orlooks like. the appearance of the monarch. Since monarchsare poisonous and any bird that has tasted one knows itthe viceroy. because it look. like the distasteful monarch. isoften left alone by experienced birds. We call this "lookingalike" mimicry.

125

Display page 26 of the Home TeacherPacket for questions 5 and 11. Forquestion 5, keep the bottom half of thepage covered so your child's attentionis directed to the top half of the page.

5. Look at this visual. Draw lines on the chart, tomatch the mimic with the animal that it imitates.(The hummingbird moth has wings similar to thehummingbird. The hover fly looks similar to the beeand also makes a buzzing sound when it flies. Thebeetle looks similar to the ant.)

6. Think back to the Finding Out activity. What de-fense did this activity demonstrate? (camouflage)

7. Look at the pictures on page 126. Which one is thewalking stick? (the one on the right) How do youthink the dead-leaf grasshopper is protected by hiscamouflage? (His enemies would not want to eat adead leaf) (NOTE: This grasshopper is native toAustralia. Some editions of the student textbookmay incorrectly call this grasshopper a butterfly.)

145

Sometimes instead of looking like other animals,animals are colored or shaped to look like theirenvironment. This is a technique that soldiers sometimes

use when they dress in mottled green clothes: camouflage,Camouflage helps conceal an animal.

One of these insects is a walking stick, Which one is it?Where do you think it spends most of its life') Can you seethe one called a dead-leaf grasshopper? With its oddlyshaped legs, it looks like brown leaves, In what ways doesthis camouflage protect the grasshopper')

Fawns of white-tailed deer have white spots on theircoats, Since they cannot run well when they arc very young,their mothers put them in a safe place and make them liedown, In tall grass or in the dappled light of the woods.fawns are hard to see,

One kind of lizard, called a chameleon, changes colorfrom green to brown. depending on the surroundings,Found only in Africa and Asia. true chameleons can blendin with bark or leaves, sand, or grass, In what ways doesthis ability help the chameleon')

126

You may wish to share the followinginteresting information with yourchild. Vine snakes of Central andSouth America are very slender snakesthat "freeze" in a horizontal positionwhen frightened. They even sway inthe breeze, just like the vines aroundthem. The sargassum fish looks justlike the sargassum seaweed it lives inbecause of the fish's leaftike growthsand the plant's bladderlike growths.

8. Look at the pictures on page 128. How do theseanimals' colors and shapes protect them? (Theirappearances frighten or warn other animals thatto eat them may be painful or even deadly.)

9. What might keep a bird from eating this moth?(The moth looks like it is watching the bird.) Whatmight make a bird find this beetle unappetizing?(It looks similar to some distasteful berry.) Dothese caterpillars look edible? (no)

10. Can you think of other animals whose bright colorsmight be a warning for other animals to leave themalone? (monarch butterfly, Gila monster, bees,cabbage beetle, coral snake)

146

Other animals' colors and shapes do not concealthem. hut reveal them, Their appearance can frightenor warn other animals that to eat them may be painfulor even deadly,

What might keep H bird from eating rhis moth?What might make a bird find this beetle unappetizing?Do these caterpillars look edible'!

128

11. Look at the visual again. Draw lines to match theanimal with its background. (The tiger matches thebackground of the grasslands. The sargassum fishmatches the sargassum seaweed of the middle At-lantic Ocean. The harp seal pup matches the iceand snow background.)

SCIENCE 4 HTE

name _

1. C••.• tulfy cut out the •• anlmll •.2. Try the animal. In each picture on page 38.3. Decide where the animal,' camouflage will belt hide them. Glue them In place.

Stonefish

Stick caterpillar

Toad

Dead-leaf butterfly

Bittern

Copperhead

~1990 Bob Jon03 Uni~or3i!y r'rcsa. Roproduc1ion prohibitod

D Sdence4N_Padlet

Le.80n32EVllultln\lth.L, ••on

Evaluating the LessonDirect a notebook activity on pages 38-39. Ask yourstudent to read the directions at the top of page 38; thentell him to carefully cut the shapes out as directed.Allow time for him to try the animals in each habitatand to complete the activity as directed.

For Your InformationExperiments have been conducted to learn more

about how camouflage helps animals to survive. A. P.di Cesnola was an Italian naturalist who performed aninteresting experiment with praying mantises. He col-lected one hundred mantises, some of them green andsome brown. He then tied twenty of the green mantisesto green plants and twenty of the brown mantises tobrown plants. The remaining mantises were tied toplants that contrasted with their own colors. After eight-een days, all the mantises whose color did not matchthat of their plant had been eaten by birds. All forty ofthose mantises whose color matched their backgroundwere still living.


38

name _

C1990BobJonesUniversilyPr,"*.R&productionprohibited

D Sdenc.e4Notebook Packet

lesson 32

Evaluating!/l8wton

Other experiments have shown that animals seem toknow instinctively that countershading helps them tohide. An experiment was made using a group of cater-pillars with the normal countershading pattern. The cat-erpillars always crawled along the top of twigs andleaves. A strong light was placed on the ground belowthe caterpillars, making the caterpillars easy to see. Thecaterpillars immediately crawled to the underside of thetwigs and leaves, enabling their counters hading to workwith the position of the light.

39

147

Introducing the LessonDirect a listening activity. Prepare your student for thefollowing story by telling him that it is a fanciful talethat takes place on another planet. In the tale he willhear different descriptions of an unusual creature dis-covered on that planet. Read the story. Give your stu-dent an opportunity to discuss the new discovery at theend of the story.

About 150,000 seglars from earth, some scientistson a delta-class planet were taking atmospheric read-ings and recording information about plant life. Thescientists became so absorbed in their work that theybecame separated from each other before any of themrealized it.

The oldest member of the group, a chemist, wastesting the acid content of the soil. Suddenly, fromdirectly behind him, he heard a muffled growl. Hisheart jumped, but he remained perfectly still. Againthe growl came. This time, the chemist slowly turnedhis head.

Behind him he saw a small beast. When the oldscientist moved his foot, the beast spit out a streamof blue liquid that instantly turned a green plantbrown right in front of the scientist. Then the creaturedisappeared into the ravine to the west. The scientistcontinued his work, but he kept a sharp lookout.

The youngest member of the research group, aten-year-old biologist, came jogging around a thickgrove of trees and came face to face with a small,five-legged animal that had a whiplike tail. The bi-ologist immediately turned on his carboscan to takereadings on this new find.

The animal snapped its tail, making a loud crackin the air. The biologist took that action as a warningand stood perfectly still. The animal watched himbriefly and then went back the way it had come.

The group leader, meanwhile, had gone back tothe space camp. He was about to go out to look forthe others when he saw them returning. The youngbiologist ran into camp first.

"I think I've discovered the first animal here. It'sa five-legged creature with a tail that it uses like awhip. I think we should call it a whiptail." He pulledout his electrosketch hand-computer to do a drawingof what he had seen.

A minute later, the chemist arrived, saying thathe had seen the first animal on the planet. "It defendsitself by shooting an acid from its mouth. I think weshould name it acid-shooter." And he began to run achemical analysis on the liquid that he had removedfrom the stricken plant.

The two scientists realized that the leader was notlistening intently. He was looking beyond them at acreature coming toward camp. It was small, but itseemed to lumber and roll more than walk. "Is thatyour new animal?" he asked.

The scientists turned around. "Yes!" they saidtogether. The creature came within 10 meters (33feet) of them and stopped. The leader switched onhis carboscan. He waited. He got no readings. Hetried again. Again no readings came on the screen.

"Well, it's definitely an animal," he said. "Butthat thing has such a thick hide that the scanner can'tget any readings!"

After some deliberation, the scientists transmittedthis message back to the main ship: DISCOVEREDNATIVE ANIMAL. NAMED IT FOR ITS DE-FENSES. TRI-HIDED ACID-SHOOTINGWHIPTAIL.

Lesson 33Weapons,Protective

Coverings, andSpecialDefenses


PreviewObjective


• 'fell the type of defense an animal uses.


• 1 sheet of drawing paper.• A Write It flip chart.

Prepare:• The following questions on the Write It flip chart for

use during Evaluating the Lesson.

1. What is the animal's name?2. Where does this animal live?3. How did you discover it?4. What does it eat?5. How does it protect itself from animals that want

to eat it?

Lesson

148 SCIENCE 4 HTE

name _

Drn a "tft.-hlded acfd-lhootlng whlptall."

"'00090bJonooUnl~oroltyPron,Ropro!l\Jctlonprohlblted.

LellOn33

D Sdence4-,- IntroduclllG t ••••LMton

Direct a discussion. Ask your student whether he thinksthat this is a good name for the newly discovered crea-ture. Guide him in reviewing the defenses he has alreadylearned about. Ask him whether the tri-hided acid-shooting whiptail uses any of those defenses previouslydiscussed. (no) Allow him to offer suggestions or ideasabout what this new animal does use to defend itself.

Direct a notebook activity on page 40. Instruct yourstudent to draw a tri-hided acid-shooting whiptail. En-courage him to use his imagination and to rememberthe things that the story told him about this creature.


40

WeaponsAnimals also have bod) parts. Or appendages that help

them defend themselves. What weapons do you see here')

Teeth, beaks. claws. hooves. tails. horns. antlers. andpincers arc some of the weapons. Do animals have oneweapon each. or do some animals have many? Can youthink of an animal that has three of these kinds ofweapons?

129

Teaching the LessonDirect a text activity on pages 129-33. Use the follow-ing question to initiate your student's interest in whathe is going to read: What three types of defenses wereused by the imaginary animal?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. What are the three types of defenses used by the

imaginary animal? (weapons, protective coverings,and special defenses)

2. Which of these defenses is most common?(weapons)

3. Name some defenses that soldiers use now or usedin the past that are similar to the animal weaponslisted on page 129. (spears, swords, etc.)

4. Soldiers use their weapons for the same reasonsthat animals use theirs. Can you name some rea-sons? (to protect their territory [countryJ, to pro-tect their children, and to protect themselves)

5. Name some protective coverings people can puton. (a suit of armor, a spacesuit, afootball helmet,etc.)

6. Name some animals that have protective cover-ings. (snail, turtle, porcupine, rhinoceros, seaurchin)

149

Antler, are bony growths that arc shed every year.Horns arc not shed; they arc a bony structure with a layerof keratin, something like fingernail>, that continues to

grow and get bigger. Moose and elk, for example, haleantlers; cows and bighorn sheep have horns.

130

7, Spines do not need to be sharp and strong to protectan animaL Some caterpillars have very fine, hair-like spines filled with a substance that causes painand itching to those who touch them, What twodefenses do these spines combine? (a protectivecovering and a special chemical defense)

8, Name some other animals that use special defensessimilar to the animals pictured on page 133, (oc-topus, electric catfish, jellyfish, cobra)

150

Protective CoveringsSome animals wear armor. A snail, for example. has (I

hard shell to pull into. Others, like the rhinoceros and thearmadillo. have tough hides. The rhinoceros also hasanother method of defense. What IS iI"

The name armadillo comes from a Spanish word for"armored." Armadillos arc covered all over except for theears and feet- by tough plates. Young armadillos haveleathery skin which hardens into a kind of armor by thetime the,y are adults. Some kinds in South America can curlup, making one round ball of protection. North Americanarmadillos dig holes Of run into thorny bushes to escapepredators. Why arc these good defenses for the armadillo"

131

Evaluating the LessonDirect a drawing activity. Give your student a sheetof drawing paper. Encourage him to use the paper todraw his own imaginary animaL Remind him to givehis creature at least one of the built-in defenses he haslearned about Direct your student to write a story abouthis creature, including the prepared information on theWrite It flip chart.

SCIENCE 4 HTE

Other animals have stif] spines all over, like theporcupine. Porcupines do not "throw" their spines, assome people think. They raise the spines up and out,sticking any enemy that comes too dose.

The sea urchin has spines all around its body. Somekinds of urchins have poison in the tips of the spines.One variety has small, tough plates around the spineswhere they join the body, allowing movement in anydirection while protect in,; the muscle.

132

For Your InformationAnimals sometimes need protection from other an-

imals of their species. Males will often fight during thecourtship season. The purpose of this conflict is to findthe strongest male to lead the herd or breed with thefemales. Females will often fight among themselves toprotect their territory. The winner will secure the bestpasture for herself and her young. In most cases, theweaker animal is not killed, but it does need some spe-cial form of defense to avoid being seriously hurt.


Special DefensesThere are some animals that release chemicals and

use electricity to defend thernvelves. This beetle sprays atoxic liquid that pruv ide-, a smoke ...creen and can blainhuman skin. It is the Bombardier beetle. Poisonous treefrogs in the tropics are brighrl, colored and boldlymarked. What defense are their show; skillS warning of'!

One kind of eel, the electric eel. can deliver a 500-volt surprise to an attacker. ., here arc nearly 500 kindsof fish and eel- that generate varying amounts ofelectricity.

133

151

FamilyTime 34

Animal Defense GameIf time permits, this game may beplayed any time after Lesson 33.

Instructions

You may wish to add more names to thelist above. Animal names should not beused more than once on the same card,and no two cards should be exactly thesame.

Direct a review game. Give each player a card andseveral game markers. Tell them that you will read aclue, and if they have the name of an animal that match-es the clue, they should cover that name with a gamemarker. The first player to mark correctly five animalnames in a row vertically, horizontally, or diagonallyshould call out "Defense." The game may be playedagain, using different clues.1. My tail makes a noise like a baby's toy, but it's a

warning and not an invitation to play. (rattlesnake)2. My two front teeth don't look like teeth at all. They

are deadly weapons. (elephant)3. My drab brown coat, dappled with white spots,

helps me hide in the shadowy sunlight of the forest.(fawn)

4. I may not be very large, but my horns and hoofsare a strong defense. (goat)

5. Few animals are as shocking as I am. (electriccatfish)

6. The inky "smoke screen" I produce helps to pro-tect all eight of my tentacles from harm. (octopus)

7. I am good to eat, if you can avoid my strong pin-cers and get through my tough shell. (lobster)

8. One of the two mammals with armor, I am veryodd-looking indeed. (armadillo)

9. I am the master of quick change; I always matchmy background. (chameleon)

10. I am a strange-looking insect that gets my namefrom the way I hold my front feet. I come in manycolors: green, brown, and even pink. (prayingmantis)

11. My striped coat helps me to hide in the tall grassesof my home. (tiger)

12. I am a great mimic; to look at or listen to me,you'd think I was a bee. (hoverfly)

13. I am very beautiful when I fly, but when I stop andfold my wings, I look old and brown. (dead-leafgrasshopper)


• Several game markers (beans, buttons, or rocks) foreach player.

• 1 card (7+" x 7+") for each player.prepare:

• The cards by using a black marker to divide theminto 1+" squares. Write one of the following animalnames in each small square.rattlesnake saddle-back caterpillarelephant praying mantisfawn dead-leaf butterflygoat crocodileoctopus Gila monsterlobster polar beararmadillo sea anemonechameleon starfishtiger sealhoverfly lionwalking stick oysterpuffer fish electric catfishporcupine blue-tongued skinkskunk hermit crabeaglecat

anteater

152 SCIENCE 4 HTE

14. In the spring I am green, but I gradually turn brownwhen the trees in which I live turn brown. Haveyou ever seen a twig walk? (walking stick)

15. I may look like a normal fish, but scare me, and Iinflate to look like a huge pincushion. (puffer fish)

16. My barbed quills will stick easily into your nose ifyou sniff me too closely. (porcupine)

17. I look like any other lizard, but no other lizard hasa tongue the color of mine. (blue-tongued skink)

18. My perfume's odor is bad enough to make eventhe bravest animal run away. (skunk)

19. My long talons and strong beak are quite effectiveweapons for me. (eagle)

20. I am usually a contented pet, but my sharp clawsand teeth will protect me if necessary. (cat)

21. I wear a green and brown saddle, but not for riding.The spines on my body are full of poison. (saddle-back caterpillar)

22. My huge jaws are full of sharp teeth. And if thatisn't enough protection, I have leathery tough skinand armored scales. (crocodile)

23. My bright pink and black colors give the warning:Stay away! My poison is powerful. (Gila monster)

24. My white coat blends with the snowy hills andprotects me from the few enemies I do have. (polarbear)

25. Although I look like a pretty sea flower, my petalsare really tentacles filled with poison. (seaanemone)

26. My hard bumpy armor protects me from fish andstorms at sea. Cut one of my arms off, and I'll notonly grow a new arm, my arm will grow a newbody! (starfish)

27. I keep my white birth coat while I live on the ice,but when I move to the sea, my coat turns brown.(seal)


Lesson 34TacticsText, pages 134-38Notebook, page 41

PreviewObjectives -----


• Name an animal's predators.• Identify the built-in defense or tactic a given animalwill use when in danger.




Direct a discussion. Display the ostrich and the fox onpage 27 of the Home Teacher Packet. Ask your studentto describe one peculiar characteristic of an ostrich.(Your student may suggest that the ostrich hides its headin the sand when it is in danger.) Generate a discussionusing the following questions.1. Do you think this is a good way for the ostrich to

protect itself? Why or why not? (Answers willvary.)

2. Does an ostrich have any body part that can beused as a weapon? (NOTE: Ostriches do have along nail on the middle toe that helps them gripthe ground when running and is also used as aweapon.)

3. Does the ostrich have a protective covering? (no)4. How might an ostrich protect itself without these

built-in defenses? (Answers will vary.)Tell your student that ostriches actually do not hide

their heads in the sand as this old fable suggests. Whenan ostrich sees an enemy, the ostrich sometimes dropsto the ground and stretches its neck out along theground, hidden by the tall grass. To someone watching,it may seem that the ostrich has buried its head. But ifthe enemy comes close, the ostrich will get up and run

154

TacticsAnimals have many built-in r1rten~es. But [he) <tho

have many tactics that help them survive.

Sometimes the simplest thing to do is hide. Manyanimals use this tactic, and some use it almostexclusively. Have you ever seen a mouse in your house?If it saw you, it undoubtedly slipped under the nearestpiece of furniture. Its response to danger was to hide.

Other animals run or JUIliJl to safety. Antelopes,kangaroos, jackrabbits, white-tailed deer, andspringboks arc fleet of foot and hoof and can oftenoutrun their pursuers. Birds and bats canjl.\' away (anda few squirrels and fishes can glide or sail brieflythrough the air). Most lizards can lip a\\'a; fromenemies; some also have tails that come off and keepwiggling in the predator's mouth while the lizard getsaway. What kind of defense would you call that"

134

away. Tell your student that sometimes the wayan an-imal acts is its best defense.

Teaching the LessonDirect a text activity on pages 134-35 and 138. Usethe following questions to initiate your student's interestin what he is going to read.1. What defense tactic does an elephant have?2, What defense tactic does the opossum have?3. How does the decorator spider defend itself?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. What defense tactic does a mouse use? (hiding)2. Why is hiding a good defense for some animals,

but the fabled hiding of the ostrich is not? (Theanimals hide their whole body, not just theirheads.)

3. What happens in the game "hide-and-seek" whena person is found? (He runs to "base.") When isrunning a good defense? (Running is a good de-fense if the animal isfaster or can run for a longertime than its predator.)

4. What tactic do elephants and many kinds of fishuse? (grouping together)

SCIENCE 4 HTE

Another tactic of animals is to group together.Many kinds of fish travel in group> called schools. Anyonc of the fish in a school can change the direction ofall by a sudden movement. The school has a> manysensors for danger as it has members. Does this helpyou understand the old saying. "There is safety innumbers"?

You may think an elephant is so big that it has IHl

enemies. But large cats like lions will attack a loneelephant. A herd of elephants. however, is safe, Theherd can protect evcn the young and the sick frompredators. What other defenses do elephants havc?

Some animals are good at hlujjillY. Perhaps youhave seen a house cat hissing at a dog. The cat's fur isbushed. even on its tail. The cat looks bigger, morethreatening than usual it's bluffing. An opossum has adifferent bluff. Instead of trying to scare its attacker.the opossum drop' down as if dead. This defense oftenworks because many predators will not cat what thcyhave not killed.

135

5. What tactic does the opossum use? (bluffing)6. What does it mean when someone is said to be

"playing 'possum"? (We usually mean that he ispretending to be asleep.) Would a person use thisbluff as the opossum does, for protection from anenemy? (Answers will vary.)

7. Call attention to the picture on page 138. Whatthings could you gather and stick to yourself todisguise yourself as the decorator spider and thedecorator crab do? (Answers will vary. Remind himthat, to be a good disguise, it must help him toblend with his surroundings.)


Still other animals pu! on disguises. The decoratorspider, for example, gathers up bits of leaves, stickingthem to itself. This behavior makes it look like a floweron a plant.

The decorator crab does much the same thing.except it docs it underwater. The salil ary glands of thiscrab produce a sticky substance that holds even in saltwater. The crab finds bits of coral. seaweed. and evenrocks and attaches them all over it; back and legs.Sometimes the crab uses IiI ing coral which continues togrow. Soon the crab looks like a moving forest of coral.

Since crabs moll. or lose their shells. the decoratorcrab has to replace ih disguise several times in its life.Also, when the crab moves to a different place, itchanges its covering, u~ing items from the newenvironment. Why is that important"

138

155

About DefensesI. Study the following scenes or examples.2. Tell what built-in defense or tactic the animal is using

in each case.3. Record your answers.

This bird lives in asnowy region. It hasbrown feathers in thesummer and white onesin the winter. What isthe ptarmigan's defense?

What does a turtle do when something taps its shell?What is the turtle's defense?

The coral snake is deadly. How does that fact helpthe king snake'?

136

Evaluating the LessonDirect a Finding Out activity on textbook pages 136.37 and notebook page 41. Instruct your student to readthe steps on page 136. Then tell him to follow thesesteps as he reads the remainder of pages 136-37.

Instruct your student to record his answers on note-book page 41. Encourage him to color the pictures re-alistically and to add a predator to each picture in thespace provided. Explain that a predator is an animal thatpreys on, or hunts for, other animals to eat as food.

156

This fish is a puffer: it puffs up and looks bigger.What defense is this?

A skunk has stripe, to warn off predators. But it ismore famous lor another kind of defense. What kind ofdefense is that"

137

SCIENCE 4 HTE

Answers

1. Study the .cene. and que.tlon. on .tudent text pig •• 137-38.2. Record your an.w ••.• In the flnt column below.3. Draw each animal'. enemy In the box with It.

name _

camouflage

It pulls ils head andlegs inside.Its defense isits armor.

It mimics the coralsnake. Other animalsthink it ispoisonous; so theyslay away from it.

bluffing

special chemicaldefense-odor

D Sdence4Notebook Packet 41


C1990 Bob Jones University Press Reproductionprohibited

Lesson 34E."luallnglheleuolt

For Your InformationGod provided a sufficient balance in nature. Allliv-

ing things are dependent upon other living things; noone animal can be considered alone. The Lord gave eachspecies some type of defense; yet these defenses do notcompletely protect the species from its enemies. If theprotection were complete, the animals that depend onthat species for food would die. God's perfect plan willallow all species to survive if we allow the plan toremain in balance.

For example, in an area where all the predators ofdeer were killed, the deer population increased untilthere was not enough food for them. Often, the deerused up the food supply to the point that no more wouldgrow. Rather than a few deer surviving in good health,all survived in very poor health. When winter came,many deer died, leaving fewer deer than before.

In another area, hunters felt that if all the coyoteswere killed there would be more quail. After all thecoyotes had been trapped, poisoned, or shot, the quailmysteriously disappeared. It was discovered that thecoyotes' true prey had been the cotton rat. This ratobtained its food by eating the eggs and young of thequail. With the coyotes gone, the cotton rat thrived,killing even more quail.

157

CHAPTER

9Light

Lessons 35-39

[)l] Light

139


In this chapter your student will learn about the char-acteristics of light, about the human eye, and about howthe eye perceives the colors that light reveals. He willexperiment with the reflection of light and learn about aspecial device, the laser, that uses the principles ofreflection.

MaterialsThe following items must be obtained before the pres-

entation of the lesson. These items are designated with an'" in the materials list in each lesson and in the Supplement.For further information see the individual lessons.

* 1 magnifying glass+ (Lesson 36)* Red, yellow, and blue play dough (Lesson 37)

159

Lesson 35Characteristics

of LightText, pages 140-43


PreviewObjectives


• Record the direction in which shadows form depend-ing on the position of the source of light.

• Record changes in the direction that light travels.


• I short candle.• I candle holder.• Matches.• 6 drinking straws.• Plastic tack.• I flashlight.• I Popsicle stick (tongue depressor or anything com-parable).

• I clear glass of water.Prepare:

• The shadow demonstration setup. Set the candle inthe holder. Put a small amount of plastic tack on oneend of each straw. On a table, set the straws uprightin a circle around the candle at a distance of 4 to 6inches. (See Figure 35-1.)

Figure 35-1

...•,~.,....~."

160

name _

TransparentOpaque Translucent

The 'peed oflight _

01990 Bob Jonet Unlvertlty Pre••. Reproduellon prohlbllltd

D Sdence4NoIebookr ••••

Leuon35

Teac:hlng lilt L ••• on 42


Direct a notebook activity on page 42. Ask your stu-dent how he thinks light travels. Ask him if he thinksmaterials in its path can bend or refract light. Tell himthat today's demonstration will help him find the an-swer. Darken the room. Using the ft.ashlight, illustratethe direction that light will take when it shines onto anopaque surface, such as a book. Ask him what happensto the light when it hits the book. (Most of the light isreflected.) Point out that when the refracted light passesto another object, it will travel in a straight line. Explainto him that if light hits an object that will let no lightpass through, that object is called opaque. Ask yourstudent to record his observation by drawing a pictureon his notebook page. Next, shine the light on a trans-lucent object, like notebook paper or a plastic reportbinder cover. Ask him what happens to the light. (Onlysome of the light passes through.) Explain that whensome of the light passes through materials like frostedglass and some plastics, they are called translucent.Allow him time to record his observation. Finally, directthe light toward a clear window. Ask your student what

SCIENCE 4 HTE

Imagine you are in a spaceship far from earth. The lightof Our sun now reaches you as a mere pinprick. The nearerstars dazzle you with their rich red and orange and whitelights. The space between the stars is a velvet black; theplanets you pass are purple, pink, and green. The lights andcolors of outer space at first surprised you. But now thesights are familiar, like the skies of earth used to be. Whatmakes all this light and dark, all this color, all this beauty?

140

happens to the light. (The light passes through.) Mate-rials like air, water, and clear glass which allow light topass through are called transparent. Ask him to recordhis observations.

Show your student the glass of water. Put the Pop-sicle stick into the water. Ask him what appears tohappen to the stick. (The stick appears to be bent orbroken.) Ask if the stick is bent or if the light is bent.(the light) Explain that the light rays have passed fromthe air to another point (the water). The change of ma-terial (from the air to the water) caused the light to bend.Explain that the speed of light in a vacuum or in air isabout the same, but is somewhat reduced in a densermedium such as water. Ask your student to write downwhat he has learned about the speed of light. Ask himhow he thinks the speed of light would be affected bycontact with opaque, transparent, or translucent objects.Would the speed of light be reduced when light travelsthrough a clear window? (no) How about through asheer curtain? (Yes, it would be somewhat reduced.)Through a door? (Yes, light would be blocked entirely.)


1. What is light?


What is Light?Light is energy. waves of radiant ellerl(Y from the sun

and other sources. There are many kinds of radiant energy:radio waves, X-rays, ultraviolet rays. gamma rays. andmore. Light rays. however. are the only ones that humanscan sec.

All the waves travel forward at the same speed 300,000kilometers (186.000 mil a second. They also move lip anddown as they travel forward, making waves. These wavesarc different lengths iwavelcngthsi. The number of wavesthat pass by a point in a second is called tllcfreqllcncL X-rays have a high frequency. What does that mean'

crest crest crest

trough trough

141

2. What are natural sources of light?3. When does a shadow occur?


1. What is light? (waves of radiant energy)2. How fast does light travel? (300,000 kilometers or

186,000 miles a second) Although the speed oflight is said to be constant, elements in its path canreduce its speed.

3. Imagine that you are standing close to car head-lights at night. The lights are very bright. Whatwould happen if your were to move several yardsaway, eventually moving one block away? (Thelights would appear to grow dim.) Do the lightsactually become dimmer? (no) What do you thinkcauses light to appear to grow dimmer? (Lightspreads out as it travels; so when the source is faraway, fewer beams will reach the eye. Thus, aperson will perceive the light as dim.}

4. What are natural sources of light? (the sun andstars) God created the sun as the chief source oflight. (Bible Promise: L God as Master) The moonand planets, which do not produce their own light,are actually reflectors of the sun's light.

161

Where Light Comes FromSome materials produce encrgy that we see as light. The

sun and the stars make such energy. They arc naturalsources of light. Somc light sources are man made, likeelectric bulbs, candles, and kerosene lamps. Anything=-natural or man made that gives off its own light isluminous. Is fire a natural source of light? How about alightning bug?

How Light ActsHave you ever seen light bend itself to go around a

corner? Light cannot bend itself; it travels in a straight linefrom its source. Would there be any shadows if light couldbend?

Perhaps you have seen straight lines of light comingdown through the trees in a forest, streaming in throughchurch windows, or slicing through holes in dark clouds. Athin line is a ray. Many rays together make a beam. Whydon't you make up a word for a group of beams?

142

5, What are some manmade sources of light? (electricbulbs, candles, and kerosene lamps)

6, How do you think an electric bulb works? Whatdo you think the little wires are for? What mightbe inside the bulb to make it glow brighter? (An-swers will vary, The filament, which is made oftungsten metal, becomes hot when electricity flowsthrough it. The bulb is filled with a gas such asnitrogen or argon, When the filament becomes hot,the bulb glows brightly.)

7, How do you think a person can see an object?(Answers will vary. There must first be a source oflight shining on it. When the light bounces off theobject or is reflected from it, the light travels tothe human eye.)

8, When does a shadow occur? (when light is blockedor absorbed) Where is the light source when ashadow forms behind you? (in front of me)

162

If light travels at 300,000 kilometers a second. how farcan it go in one minute'!

300,000 kilometers x 60 seconds = 18,000,000 kilometers a minute

Imagine how far light could travel in a year! It can go 9 V,trillion kilometers (six trillion miles). This distance isknown as 11 light-year. Three and one-third light-yearsmake a parsec. How tong is a parsec?

Light will keep traveling in a straight line untilsomething stops it or changes its direction. If light hits anobject that will let no light pass through. that object iscalled opaque. Can you think of something that blockslight? Docs a rock? How about a soccer ball? Rememberhow a solar eclipse happens'! The opaque moon keeps usfrom seeing the sun for a little time. Opaque objects makeshadows by absorbing light.

Some objects let light pass through. Such objects arecalled transparent. Look around the room. Whattransparent objects do you see'? How would the room bedifferent if all these objects were made opaque?

143

Conclude the discussion. Ask your student how shad-ows can help him to determine direction. For instance,in the morning, if he were to face east toward the sun,which way would his shadow point? (west) If two chil-dren were to go outside late in the afternoon to standside by side, one facing east and one facing west, whichdirection would both shadows face? (east) Be sure thatyour student understands that shadows always form di-rectly behind the object that blocks the source of light.Tell him that the following demonstration will showwhat he has just learned,

SCIENCE 4 HTE

name

Shade the are.s where the shadow, appeared.

~

!J

~

~~ ~~~

~~l990BobJonesUnlversUyPress Reorodur.l.nnp,nh'b'19';I.

D Sdence4 Lesson 35

Notebook Packet e.,.JI,I.titlglheltuon 43

Evaluating the LessonConduct a demonstration of shadows. Turn out thelights and light the candle you have placed in the centerof a circle of upright straws. Point out that the shadowsform behind the straws, illustrating that light travelsstraight from its source. If light could curve to go aroundthe straws, the shadows would disappear.Direct a notebook activity on page 43. Remove thecandle and holder from the center of the circle andrearrange the straws, placing the candle in front or tothe side of the grouping of straws as illustrated on thenotebook page. Instruct your student to record his ob-servations about the direction in which the shadowsform depending on the position of the source of light.


For Your InformationThis lesson has dealt with light that is visible. There

are several other forms of radiation, such as radio(Hertzian) waves, infrared rays, ultraviolet rays, X-rays,gamma rays, and cosmic rays, that are invisible to thehuman eye. These forms are all classified as electro-magnetic waves, and all, including light rays, travel ata speed of 300,000 kilometers (186,000 miles) a second.Although the waves travel at the same speed, they differin length and in frequency. The wavelength is the dis-tance between corresponding parts of two of the waves.The frequency is the number of wavelengths that canpass a given point in a second. Electromagnetic waveswith long wavelengths, such as radio waves, have a lowfrequency. Electromagnetic waves with short wave-lengths, such as X-rays, have a high frequency.

163

Lesson 36The Human Eye


Objective

Sit near a bright light and tell your student to watchthe pupils in your eyes. Let someone else turn off thelight. Ask your student what happened to the pupils.(They become larger.) Why do you think the pupilsbecome larger? (When the light is dim, the pupils willwiden to let as much light as possible into the eye.)Then ask for the light to be turned on. Ask your studentto notice what happens to the pupils. (They becomesmaller.) Explain that there are muscles set in a ringaround the pupil which contract (or squeeze), pullingthe pupil together and making a smaller opening. Whenthose muscles expand, they make the opening larger.

Preview


• Record his observations about optical illusion.

MaterialHave available:

• 1 magnifying glass.*t• Home Teacher Packet, p. 28 (optional).• 1 pencil.

Introducing the LessonDirect an observation activity. Tell your student thatthere are some parts of the eye that are visible, andmany more parts that are not normally seen. Ask wheth-er he knows what part gives the eye its color. (the iris)Ask him what part of the eye people remember best.(the iris) The pupil, the opening in the iris, lets lightinto the back part of the eye. Ask your student why hethinks the pupil appears to be black. (It appears to beblack because no light comes from it.)

Figure 36-1

Lesson

Direct a demonstration. Explain that a magnifyingglass can help your student understand how the eyeworks. Ask him to look through the magnifying glassand describe what he sees. Tell him to choose an objectto focus upon, then close one eye and hold the glass infront of the object. Now, extending the arm, move theglass away from his eye. At some point the picture willturn upside-down. (NOTE: See Figure 36-1.) Tell himthat the lens of the eye turns incoming images upside-down but that the brain makes the images right-side-upagain.

164 SCIENCE 4 HTE

How Do We See Light?Imagine a telescope ih.u would be srnall cnough to fit

into your pocket, powerful enough to let you see an objectseveral miles away, and yet able to adjust itself to show youall object two inches away, Imagine also that this telescopecould repair minor damage itself. perform its OINIlupkeep,and could not be duplicated 11) any science laborator-, inthe world. How much do you think such a wonderfulmachine would be worth? It would be priceless.

God has given you 1WO such marvelous pieces ofequipment your eyes. Scientists cannot explain everythingabout how thc eyes work. They can (111) describe whathappen> when light enters the eye.

Your eyeball is a lillie bigger than the ball you playjacks \I ith. It has three layers. The sclera. the white of theeye, keeps the' shape of the eye. It is white except for arransparcnt part. the cornea. which let-, light in.

The second layer i-, the choroid. a thin tissue \\ ith bloodvessels in it. Part ot this layer forms the iris, The iris isprobably the part of someone", eyes you notice andremember. What part of the eve is that" The iris has

144

muscles that make the small opening in its center changesize. If the light is bright, this opening, the pupil, gets small:if the light is dim, the pupil opens wide to let in as muchlight as possible.

The changes in the pupil protect thc innermost part ofthe eye from getting too much light. The inside layer is therelit/a. It has thousands of phmoreceptors. nerve cells thatarc sensitive to light. Photoreceptor comes from two Latinword parts: photto)- meaning "light," and recipere meaning"to receive." Can you think of some other words that havephotto): in them" What do they have to do with light"

The photorcceptors an: connected to the optic nervewhich carries nerve messages. or impulses, to the brain. Thebrain then interprets the messages.

145

Teaching the LessonDirect a text activity on pages 144-46. Use the follow-ing questions to initiate your student's interest in whathe is going to read,

1, What is the white of the eye called?2. What carries the messages from the eye to the

brain?3, How does the shape of the eyeball affect your

sight?Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read,

purpose of these bones are? (Answers will vary,These bony cavities protect the eye because eachfunnel-shaped hole contains blood vessels, nerves,tear glands, and muscles that move the eyeball,There is also connective tissue around the eyeballas well as a padding offat that cushions the eyeballfrom hard blows.)

4, What part of the eye has color and shows throughthe cornea? (iris) The color comes from small bitsof pigment behind the iris.

5, A clear sac of tissue is behind the pupil, What isthis part? (lens) It is shaped like a round buttonwith bulges in front and back, What is the purposeof the lens? (to focus the light that enters the eyeand to form a picture at the back of the eye)

6, The most delicate part of the eye is the retina,which covers the back four-fifths of the eyeball,What are the sensitive nerve fibers in this partcalled? (photoreceptors)

7, What are the photoreceptors connected to? (theoptic nerve) What is the purpose of the optic nerve?(It carries nerve messages to the brain which in-terprets the messages)

8, Direct his attention to the diagram on page 146,What is the description of the eyeball of a near-sighted person? (longer than normal) An image of

165

Direct your child's attention to the di-agram of the eye on page 145 as youdiscuss the parts of the eye,

L What is the white of the eye called? (sclera[sklir ' g])

2, Which part is transparent like glass? (cornea) To-gether the cornea and the sclera form a relativelytough cover for the delicate parts inside the eyeball,

3, Move your fingers around the edge of your eye.What do you feel? (bones) What do you think the


Behind the pupil is the lens, a clear sac of tissue aboutthe consistency of jello. Two muscles hold the lens andchange its shape. When you look at something close, themuscles push in on the lens, making it thicker When youlook at something far away. the muscles relax. and the lensflattens out.

If the eyeball is longer or shorter than normal. then thelens cannot focus the light on the retina. The ray, focus infront of the retina in a long eyeball. causing nearsighted-ness. In a short eyeball. the rays focus behind the retina,causing farsightedness. Glasses or contact lenses help theeyes' lenses focus light correctly.

correctionnormaleye •• none requrred

farsightedeye

Most of the space behind the lens is filled with a clearsubstance something like jelly. It is called the vitreoushumor. Vitreous comes from the Latin word for "glass";humor comes from a word meaning "liquid." Why isvitreous a suitable description of this substance?

146

a faraway object will be blurred, What kind of lenswill correct nearsightedness? (concave) A concavelens is thinner in the middle than at the edge.

9, What is the description of the eyeball of a farsight-ed person? (shorter than normal) What kind of lenswill correct farsightedness? (convex) A convexlens is thicker in the middle than at the edge,

Conclude the discussion. Ask your student whether hethinks he sees the same way from both eyes, (Answerswill vary.) Explain that two eyes working together willsee more than just one eye sees alone. Illustrate byasking him to hold his pencil at arm's length so that thewriting on the pencil is barely visible on the left side.Ask him to describe what happens when he closes firstone eye and then the other to see the writing. (The lefteye will see a bit more to the left than the right eye.)

166

name _

Describe two ways that you see each picture.

~

I see three blocks in a corner, and I see a stack01 live blocks with three on the toe and two on

the bottom.

$ Isee a white cross and a black cross.

••• •• Which flower center is bigger?

••• ••• The~ are the same size .••• ••~~ Look at all four bars at

once. Do the lines appear

~~ to curve? yes

~~ Check with a ruler.

~~

·,t90SobJon'IUnlv'r.IIyPrln.Reproduc'lonpro~lblltd

D Sdence4Note_ PACket

le •• on38Ev.lu.tingt!1eLeuon 44

Evaluating the LessonDirect a notebook activity on pages 44 and 45. Ex-plain that the eyes sometimes play tricks on the mind,Ask your student to look at the notebook page and writehis observations about the optical illusions, or visualtricks, he sees there, Explain that there are two ways tolook at the blocks and the octagon, His brain will tireof looking at the pictures one way and will automati-cally change the way he is seeing the images.

Discuss your student's reactions to the optical illu-sions after he completes his notebook page.

SCIENCE 4 HTE

Is the hat as tall as it is wide? Use aruler to find out. yes

•• --•• •

•• • • • •

Are these lines curved? no

Which line appears longer, a or b?

b

Now measure.

They are the same length.

45

EnrichmentTurn over the Braille alphabet on page 28 of the

Home Teacher Packet and lay it on a sheet of heavypaper. Looking at the alphabet from the backside of thecopy, use a dull pencil to make indentations through thecopy onto the sheet of heavy paper. (NOTE: Becauseyou are working from the back of the paper, the raisedpart of each dot may be felt on the front of the heavypaper, and the alphabet will be readable in the correctleft-to-right order.)

Show your student a copy of the Braille alphabetyou have made. Explain that blind people "read" thedots with their fingers. Encourage him to learn a few ofthe dot patterns.


For Your InformationEye tests are required regularly of nearly everyone.

Good sight is a requirement for many jobs and dailyroutines, such as driving a car. The standard test foreyes is the Snellan Chart, which consists of eight linesof letters of varying size. The person being tested stands20 feet from the chart and reads the letters, first withone eye and then the other. People with normal visioncan read the bottom, smallest line at a distance of 20feet. If a person can see only the top line (the largest E)clearly, his vision is said to be 20/200, which means hehas to be 20 feet from the chart to see what others cansee at 200 feet.

Although the eye is irreplaceable, parts of it can besurgically replaced or repaired. Transplants of lensesand corneas, for instance, are very often successful inrestoring sight to a visually impaired person. The mus-cles that move the eye are defective in some people. Acondition known popularly as lazy eye is fairly commonin children and can be corrected by placing a patch overthe good eye until the weaker one develops morestrength or by doing visual exercises to strengthen theweak eye.

167

Lesson 37ColorText, pages 147-52Notebook, page 46

PreviewObjective


• Explain the role of light in producing color.


• 1 prism] or 1 clear drinking glass.• Water.• Red, yellow, and blue play dough.* (NOTE: SeeFamily Time 28 for play dough recipe.)


Introduce an activity. Tell your student that color isan important part of daily life. People look at the colorof many objects to determine certain characteristics.Ask your student what the color of meats and mostproduce in the grocery store indicates. (Answers willvary. We judge the freshness of meats and produce bytheir colors.) Ask how color can help a mother tellwhether a child is ill. (by his flushed or pale face) Askhim what a dark, overcast day would tell a person. (tocarry an umbrella) Ask why a gardener would look atthe color of his plants. (to determine their health) Lan-guage is full of common references to color. If you say,"Jane is seeing red," the listener would assume thatJane is angry. Ask your student what you would meanif you said, "I feel blue today." (that you feel sad) Askhim to think of other examples. (These may include"gray day," "green with envy," "white with fear,"and "you're yellow.") Ask him which color he asso-ciates with royalty. (purple)Direct a notebook activity on page 46. Ask your stu-dent to color the first part of the notebook page accord-ing to the directions.

168

name _

Color WheelColor 'h. eeter whlllaeeording to Ih. colora n.mld In ,ech HCtIon. Color ttM outer t1ng by combiningthe two cOlart that lIeh .Ictlon OWlrI.pI to mike I new color.

Combine The opposite of

red with blue to get purple blue is orange

blue with yellow to get green red is green

yellow with red to get orange yellow is purpte

Other Combinations

________ with to get _

________ with to get _

_____ with to get _

~1990 Bob Jones UnIverSIty Preu. ReproductIon p.oh'b,lad

D Science 4Notebook Packet

Lesson 37TeachIng the ltllOt"l

Give your student small amounts of red, blue, andyellow play dough. Tell him to try to pinch off equalamounts of the colors and mix them according to thedirections in the section of his notebook page labeledCombine. Ask him to complete the next section by look-ing at the color wheel.

Ask your student how colors that are close to eachother on the color wheel make him feel. (They have apleasing effect when seen together.) Colors that are op-posite on the wheel are called complementary. Ask himif complementary colors look good together. (yes) Askhim how colors that are far apart on the color wheelmake him feel. (They may make the viewer feeluncomfortable. )

If time permits, you may have yourchild work the last section of the note-book page Other Combinations. Hewill mix the primary colors of playdough (red, blue, yellow) and the sec-ondary colors (orange, purple, green)to create his own colors, two additivesat a time. Ask him to record his obser-vations in the blanks on the notebookpage. You may make the secondarycolors by mixing the play dough aheadof time.

SCIENCE 4 HTE

What Is Color?If opaque objects keep light from passing through,

where does the light go? Does it all sink into the object?When light hits an opaque object, some of the light wavessink in are absorbed -and others are sent back to oureyes. The ones sent back are the only ones we see as color.Look around the room until you see a red object. Thatobject looks red to you because it has absorbed all lightwaves except the ones that your eye sees and your brainreads as red.

What Is Not Color?Black objects absorb most light rays. Is black a color

then? Complete black is really the total lack of color. Whatdo you suppose white. the opposite of black. is'! White is allcolors being reflected together.

147

When light strikes an opaque object. you see thereflected light as color. But what happens to the light that isabsorbed? It is changed to heat. What colors would helpyou on cold days? What color would be best to wear on hotdays?

If you have ever seen a ray of light coming in through awindow or down through the trees. you probably rememberit as bright and white. Is white the color of light then?Indeed. is white a color') Can there be color without light?

Light waves have color White is a mixture of all lightwaves, To see color. we must see light waves reflected.

Remember the imaginary trip in space at the beginningof the chapter" The space between the stars was unlit eventhough the SIal'S arc putting out great light. The darkremains because there is nothing in empty space, not evenenough dust. to scatter and reflect the light of all thosestars.

148

Teaching the LessonDirect a text activity on pages 147-50 and 152. Usethe following questions to initiate your student's interestin what he is going to read.1. What causes objects to have color?2. What makes the sky look blue and the sun look

yellow?3. What is a spectrum?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Can you see any color in the darkness? (no) If the

light is turned on, can you see color? (yes) Did thecolored objects in the room undergo a change whenthe room was dark? (no)

2. What do you think allows your eyes to see color?(light)

3. What causes objects to have color? (The color ofan object depends on what kind of light rays itreflects.) Why does a leaf look green? (The color-ing matter in the leaf absorbs or traps all lightexcept green rays. These reflected rays stimulatethe eyes to send a green signal to the brain.)

4. Is white the color of light? (Your student's answerwill vary. Most light comes from the sun. The sun's

light is white, which is actually a mixture of all thecolors. If you change the color of light, you changethe color of the object it shines upon.)

5. Which color is best to wear on cool days? (Sinceblack absorbs light, it helps a person to retainwarmth.) Which color is best to wear on a hot day?(White is most comfortable because it reflectslight.) A person can see that colors containinggreater degrees of white are the "cooler" colorsto wear. Those that appear darker are "warmer."

6. What makes the sky look blue and the sun lookyellow? (the scattering of light on dust)

7. Look at the old saying on page 150. Why is itaccurate? (Good weather is ahead when the sky isred at night because the light passes through moredust than moisture. Bad weather is ahead when thelight passing through moisture-filled air makes thesky appear red in the morning.)

8. What is a spectrum? (bands of light)9. What color has the shortest wavelength? (violet)

What color has the longest wavelength? (red)10. What do we call a spectrum in the sky? (rainbow)


What Reveals ColorYou may have noticed \\ hen you were shining the

flashlight in the dark room that YOU could see the beam orlight. Earth', air i-, not nearly so tree ot dust and otherparticles as outer 'pace is. f'he light waves from theflashlight bounce oil' particles in the air, and we call thensee the beam. lhc dust is scattering the light waves.Sunlight that streams down through ircc- and in throughwindows also bounces off particles in the air. and so we"see" the light.

This scattering of light on dust is what make, our skylook blue and our sun look yellow. When the sun's lightenters our air during the middle or the day. the wavelengthsarc coming down from fairly straigh: above. The dust in theair catches and scatters •..orne of the shorter bluewavelengths. The sky then looks blue. The red and yellowwavelengths. being longer. pass through. So the SUJ1 looksyellow to LIS.

Conclude the discussion. Ask your student to readGenesis 9:8-17, Point out that every time he sees arainbow in the sky, that bow is a reminder of the cov-enant that God will never again send a universal floodto destroy the world, In that promise as in all others,God is faithful to keep His Word. (BAT: 8a Faith inGod's promises) Ask him to name other promises fromthe Bible,

170

149

When the sun is low in the sky. the light comes in at anangle and must pass through more dust. More bluewavelengths are scattered out of the light. making the sunlook orange or red. Sometimes clouds with lots of water inthem absorb blue and green wavelengths. How does the skylook then? How do these facts fit with this old vaying:

Red sky at night,Soilorsilelighr.

Red sky at morning,Sailors lake warning,

Remember our imaginary trip in space again. Why doyou think that the stars and planets seemed so bright andcolorful?

150


The following activity will work onlyon a sunny day, Some people say thatthe spectrum has seven colors, where-as others say that it has only six. Thecolor indigo appears between blue andviolet but few people identify it.

Direct a Finding Out activity on page 151. Ask yourstudent to read the steps in the Finding Out box andthen to get a piece of white paper.

Give him a prism or a clear glass containing water.Instruct him to turn the prism or glass until he can seebands of color on the paper. Ask him to identify thecolors on each side of the band, (red-although it mayblend so closely with the orange that your student willsay orange-and violet, or purple) Ask him to identifyall the color bands that he sees on the paper. (red,orange, yellow, green, blue, violet) Then discuss yourstudent's ideas about the color with the shortestwavelength,

SCIENCE 4 HTE

About ColorI. On a sunny day, take a prism and a piece of white

paper outside or to a window.

2. Hold the prism to the light and put the paper under it.

3. Turn the prism until you can see bands of color On thepaper.

4. What color shows up on the one side? What colorshows up on the other side? Which color do you thinkhas the shortest wavelength? Why'!

151

For Your InformationWhen a person watches color television, his eyes

blend the three basic colors to produce the wide rangeof colors he sees. The television tube is covered bymillions of dots that radiate red, green, and blue light.These fuse in the eye to produce the sensations of colorthat the brain registers. Color printing is also possiblebecause of dot structures. If you were to hold a strongmagnifying glass close to a color photo in a newspaper,you would see the dots that make up the colors.

The human eye is equipped to discern color bymeans of cones in the retina. The rods perceive lightbut not color. They react in dim light. There are threetypes of cones, each one reacting to one of the threeprimary colors of light. Color perception occurs as fol-lows: When red light enters the eye, the red sensitivecones trap it and undergo a chemical change that sendsa nerve signal to the brain. The brain recognizes thesignal as red. When all three types of cones react, thebrain recognizes white. A colorblind person is one whodoes not perceive color normally. A completely color-blind person sees everything in shades of gray. Thiscondition is very rare. Many people who are considered


When sunlight passes through a prism, the waves arebent and the light is broken up into bands of colors. Thesebands of light together make up a spectrum. To our eyes,the spectrum seems to have only six or seven colors. Buteach hand in the spectrum has a huge number of differentwavelengths in it. What do you think would happen tothese colors if you used a second prism to bring them allback together?

Violet light has the shortest wavelength. It alwaysappears on one end of the spectrum. Why does red appearon the other end?

Sometimes a spectrum appears in the sky. What do wecall it then? What do you think is acting as a prism in theair to break up the light into its colors? Water drops can bcmany little prisms after a rain. How do you think you couldmake a rainbow appear')

152

colorblind can actually see colors, but not the way otherssee them. Most of these people see blue normally buthave trouble seeing reds and greens. For instance, theymay be unable to 'see a small piece of red paper on asheet of black paper.

171

Lesson 38Reflection

Text, pages 153-56

Preview LessonIntroducing the Lesson

Direct an activity. Show your student the black paper,the white paper, and the metal pan. Ask him which ofthe three is the best reflector. (the pan) Then show himthe pan and the mirror. Ask him which is the betterreflector. (the mirror) Ask him what makes the differ-ence. (The amount of reflection depends on the materi-als involved.) Ask your student what kind of surface thepaper has. (Answers will vary. Even the slickest papershows up rough under a microscope.) Ask him whatkind of surface the mirror has. (Answers will vary. Ithas a shiny, smooth surface.) Then ask him what kindof surface reflects more light. (A light, smooth, opaquesurface will reflect more light than a dark, rough,opaque surface.) A patch of dirt will reflect little lightcompared to a sheet of metal. A rough, unfinished boardwill reflect less light than a highly polished board, evenif the boards are of the same type of wood.Conclude the activity. Ask your student what his re-flection in the mirror is called. (image) Hand the mirrorto him and ask him to wink his right eye. Ask whicheye winked in the mirror. (the left) Ask him ifhe knowswhy the left eye winks in the mirror when he winkedhis right eye. (Answers will vary. When a person looksinto a mirror, the image facing him is reversed.)


do the following:• Identify various surfaces as good or poor reflectors.• Define concave and convex with reference to mirrors.


• 1 piece of shiny metal (e.g., a metal baking dish).• 1 mirror.• 1 metal spoon (optional).• 1 flashlight.• 1 sheet of black paper.• 1 sheet of white paper.• Home Teacher Packet, p. 29.

172 SCIENCE 4 HTE

$smooth surface rough surface

ReflectionYou already have seen that some object> reflect more

light than 011,or5. But SOI11eobjects reflect light helle!' thanothers. Which can you see yourself in more clearly apuddle or a white china plate? Can you vee yourself at all ina piece of notebook paper'! Whal kind of objects can yousee yourself in" What is alike about all of them?

The best reflectors are smooth, shiny. opaque object>.Polished metals like chrome and sih or send light back well.Good mirrors arc sheets of clear glass backed usually bysilver Light passes through the glass but nearly all of it issent back by the silver. When the wavelengths hit themirror, each ray is sent back evenly with all the others. Thebeam, although it changes direction, keeps the same form.So the image from the mirror looks like what is in front ofthe mirror. If the mirror is flat and even. the reflection willbe clear.

154

Teaching the LessonDirect a text activity on pages 154-56. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. What makes a mirror a good reflector?2. What are two types of mirrors that are not flat?3. What is a periscope?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. What makes the mirror a good reflector? (Nearly

all of the light that passes through the transparentglass is bounced back by the opaque metal.)

2. If the mirror is flat and even, what kind of imagewill be reflected? (a clear image of the same sizeas the object being reflected)

3. What kind of mirror curves inward? (concave)What happens to your reflection in a concave mir-ror? (It is smaller and upside-down or a bit biggerif the curve is slight.)

4. What everyday items can you think of that useconcave mirrors? (headlights and flashlights)

5. What kind of mirror curves outward? (convex)What happens to your image in a convex mirror?(It is smaller and wider and seems faraway.)


Curved MirrorsSome mirrors are not flat. They curve in or out. Have

you ever looked at your reflection on a shiny knoh or abowed window? What happens to your image? Did youever go into a building with curved mirrors at anamusement park'>

Mirrors that curve in are called concave. If they curveonly a lillie, the reflection is made a bit bigger. If they curvein a lot. the image gets smaller-and turns upside down.Cars have concave mirrors on them. Can you guess where?Around the headlights. These metal mirrors help throw thelight out in front of the car.

Mirrors that curve out are convex. Things in convexmirrors appear smaller and farther away than they would inflat mirrors. Convex mirrors take in a wider view. Wherewould such mirrors be useful?

Angles of ReflectionWhen light is reflected it changes direction, but it still

travels in a straight line. Do you think, then, that youwould be able to predict where a beam of light will reflectto? Yes, you can. If a light shines on a smooth, opaquesurface at an angle, it will bounce off in the oppositedirection at that same angie.

155

6. What can you think of that uses convex mirrors?(They are used on some cars and trucks to providea wide-angle rearview image and in some storesto provide an image of the aisles of merchandise.)

To help your child understand concaveand convex mirrors, you may give hima metal spoon. When he looks into thebowl of the spoon, his reflection willbe similar to a concave mirror. Whenhe looks into the back of the spoon,his image will be similar to a convexmirror.

7. What instrument uses mirrors to redirect the pathof light? (periscope)

Display page 29 of the Home TeacherPacket showing a simple periscope.

8. How does this simple periscope reflect the imageto the viewer's eyes? (using two mirrors) Trace thepath that the light will take through the periscope.

9 Name some people who have used periscopes. (sol-diers in the Civil War, sailors in submarines, andhunters)

173

Periscopes are instruments that let you see light that isnot traveling straight into your line of vision. They can, inshort, permit you to see around corners Of over walls.

Periscopes use the facts that light always travels in astraight line and that it can be reflected. Light travels into aperiscope, is reflected by a series of mirrors or prisms, andpresents an image to the \ iewer. Soldiers in the Civil War,sailors in submarines, and sometimes hunters have usedperiscopes.

Name some things that do not reflect images at all.What is alike about all those objects'} They are notcompletely smooth, are they? Even the slickest paper showsup rough under a microscope. And how many of theobjects are shiny? Probably not many. So what do youthink makes an object a poor mirror') Some surfaces, likesnow, reflect a lot of light. But, unlike a mirror, the snow isrough and sends light back in all directions. We see all thelight, but it appears as the color white, not as an imagereflection.,.Yea, the darkness hideth 1101 [rom thee: but the nigh!shineth as the da.l': the darkness and the ligtu are both alike10 thee. ,. Psalm 139:12

156

Conclude the discussion. Ask your student to readPsalm 139:12 from his Bible. Ask him whom this verseis speaking of. (God) Ask him why darkness and lightare alike to God. (He can see us at all times; the dark-ness does not affect what He can see. Darkness cannothide us from Him.) (Bible Promise: H. God as Father)

Evaluating the LessonDirect a Finding Out activity on page 153. Direct yourstudent to read the activity before beginning. Instructhim to get the flashlight and small hand mirror. Darkenthe room. Allow him to hold the flashlight straight infront of him and turn it on. Ask him to answer thequestion at the end of Step 2. You will need to hold theflashlight and allow your student to hold the mirror infront of the beam as directed in Step 3, and then contin-ue with Step 4.Discuss the activity. Ask your student how he was ableto direct the light beam to another spot in the room. (bychanging the angle of the mirror used to reflect it)Emphasize the fact that although the light changed di-rections, it still traveled in straight lines.

174

About ReflectionI. Get a flashlight and a small hand mirror.

2. In a dark room turn on the flashlight. Where docs thebeam hit?

3. Now hold the mirror at an angle in from of the beam.Where does the beam hit?

4. Now choose a point in the room and try to angle themirror so that the light will be reflected to it.

5. What do you have to do to direct the light 10 anotherspot?

153

For Your InformationWhen light is reflected, it changes direction but still

travels in a straight line. When a ray of light strikes amirror head on, the ray is returned straight back. Whena ray of light strikes a mirror at a slant, the ray isreflected at a slant. The ray striking the mirror is calledthe incident ray. The law of reflection states that theangle of incidence is equal to the angle of reflection.This law is applicable to all smooth, polished surfaces.It does not apply to rough surfaces because each strikingray is reflected irregularly from a rough surface.

When light strikes a very smooth surface, the lightis reflected regularly to the eye, and a glare results. Acoarser surface scatters the light and eliminates glare.This principle is useful in lighting a room in a home orschool. Direct lighting, such as would be produced froma plain, unshaded bulb, causes much glare. A frostedbulb scatters the light and helps to cut down on theglare. Semidirect lighting involves a translucent bowlor shade that directs some light to the ceiling. Withindirect lighting, most of the light is directed toward theceiling or a wall and is then scattered all over the room.Indirect lighting provides the least amount of glare andis thus easiest on the eyes.

SCIENCE 4 HTE

Lesson 39LasersNotebook, page 47

Preview LessonObjectives Introducing the Lesson

Direct a discussion. Ask your student what he thinksof when he hears the word laser. (He will probablyassociate lasers with modern warfare.) Ask him if heknows the meaning of the word laser. (Answers willvary.) Explain that lasers are the world's most brilliantsource of light; some lasers are even brighter than thesun. Talk about concentrating light in a small area. Askhim whether the heat from light focused on a small areawould be greater than or less than that of the sameamount of light shined on a large surface. (greater than)Tell him that the laser is a device that intensifies lightby narrowing its focus.

The word laser is an acronym or a word formedfrom the initial letters of a name. Write the followinginformation on the Write It flip chart for your student.

LightAmplification byStimulatedEmission ofRadiation

Direct an observation activity. Demonstrate the prin-ciple of the laser. Ask your student if he remembers inwhat direction light from an object spreads out. (alldirections) Darken the room and then turn on a smalllamp. Remove the shade and note the direction of thelight. Next, wrap a piece of dark construction paperaround the bulb. Ask your student in what direction thelight rays spread now. (one direction) Pick up the lampand point it in different directions to send "beams" oflight. Tell him that the laser works similarly. It channelsthis light into single beams of great energy. Ask him ifhe can estimate the size of a laser beam. (The beam maybe as narrow as a pencil but can be projected over adistance of thousands of miles.)


• Explain the purpose of the laser.• List two uses of the laser.


• A Write It flip chart.• 1 lamp with shade.• 1 sheet of dark construction paper.

This lesson uses a notebook page buthas no accompanying pages in the stu-dent text. As a supplement to the fourpreceding lessons on light, it introduc-es lasers and helps your child under-stand the principles on which lasersoperate.


name _

L1tt the pUrpoMS of the I••• r.

to amplify light rays

to locus light rays

Using the d",m of lhe pulsed ruby teser, fill In the blanks with the correct letter.

_b_ reflecting mirror

_e_ laser light

_c_ partially transparent mirror

_a_ flash lamp

_d_ ruby

industry, communication

medicine, navigation

~19908obJonesUnjvels'lyPfe" Reproducljonprohibiled

D Sdence4Notebook'''''

Lesson 39

EvetUltlngtIaL."on 47

Figure 39-1

reflectingmirror

trigger electrode

flash lamp

Ruby Laser

176

ruby rod

partially

Teaching the LessonDirect a notebook activity on page 47. Direct yourstudent's attention to the diagram on page 47. Tell himthat the laser you will be discussing today was the firstone made, the pulsed ruby laser. Explain that the flashlamp in the laser sends out a burst of light. It lookssimilar to a coiled florescent tube. Ask him to locate theflash lamp on his diagram. (NOTE: See Figure 39-1.)

As your child locates each part of thelaser, allow him time to fill in the blankwith the correct letter.

Part of the light is absorbed into the ruby crystal.The crystal looks like a tube. Ask your student to locatethe crystal on his diagram. The absorbed light in turnsends out red light in all directions. The red light thenstrikes two mirrors. Ask your student to look at thenarrow end of his diagram and to find a small circulardisc. Tell him that this is the reflecting mirror. Ask himto find another circular disc at the other end of hisdiagram. Tell him that this is the partially transparentmirror. The red light is bounced back and forth manytimes between the two mirrors and is greatly amplified.Some of the red light goes through the partially trans-parent mirror and becomes the highly focused beam wecall a laser. Ask your student to locate the laser light onhis diagram.

metal holder

laser light

SCIENCE 4 HTE

Discuss the uses of the laser. Tell your student-that thelaser can be used to cut through metal and similar ma-terials. In this way it is helpful in industry. Ask him ifhe knows how a doctor might use a laser. (Answers willvary.) A doctor might use it in surgery to bum awaydiseased body tissues, such as a tumor in the eye. Laserbeams are used in communication to transmit TV sig-nals and voice messages. In astronomy, lasers aid infiguring distances. Tell your student that the exact dis-tance to the moon was calculated in this way. Lasersare also helpful in providing information about themoon's orbit, surface, and interior structure.

Evaluating the LessonDirect a notebook activity on page 47. Instruct yourstudent to list the purposes of the laser. Then ask himto write down two uses of the laser.

EnrichmentIf your student shows interest in the use of lasers in

modem warfare, you may show him a kaleidoscope.The destructive capabilities of the laser in warfare allarise from the simple principle of reflection. On a sim-pler level, the principle of reflection creates patterns ofimages in a kaleidoscope. Allow your student to try tocount the number of images he sees.

Explain that just as the light rays in the kaleidoscopezigzag from mirror to mirror, so the laser beams fromthe weapons reflect from mirror to mirror to hit oncom-ing missiles.

For Your InformationA laser device generates and amplifies visible, in-

frared, or ultraviolet light. Light spreads out from asource in all directions and in a number of frequenciesand waves. Lasers focus these waves of light into beamsof great energy. There are two types of lasers: solid andgas. Solid lasers usually generate sudden bursts of light.Gas lasers usually produce continuous beams of light.

The laser is capable of generating enough heat (over10,000 degrees Fahrenheit) to bore a hole in a diamond.In astronomy, distance may be calculated to an accuracyof 15 em (6 inches). The McDonald Observatory, alunar ranging facility now replaced by the observatoryat the University of Texas, once provided 90 per centof all data received by ranging stations around theworld. From 1969 to 1984 it was the only instrument inthe world that provided accurate earth-moon distances.


CHAPTER

10Machines

Lessons 40-43

~Machines

157


This chapter presents the six simple machines thatmake up all machines: the lever, the wheel-and-axle, thepulley, the inclined plane, the wedge, and the screw. Ineach lesson your student tries to solve the problem ofgetting a buried treasure by using a different simple ma-chine. As he studies each machine, he looks for examplesof that machine at home.



* Preweighed packages totaling 20 pounds (e.g., four5-pound bags of potatoes) (Lesson 40)

* Wire cutters (Lesson 41)* 1 crank-type pencil sharpener (optional) (Lesson 41)* 1 lever-type can opener (Lesson 42)* 1 pull spring scale] (Lesson 42)* 1 set of gram weights or standard mass set] (Lesson

42)* 1 box decorated like a treasure chest and filled with

snacks to be shared at the end of the lesson (optional)(Lesson 43)

179

Lesson 40 Lesson

Inclined Planes Introducing the Lesson

Preview

Introduce a treasure hunt. Before displaying the treas-ure chest visual on page 30 of the Home Teacher Packet,make sure that the outlines of the hole and the treasurechest are covered by a blank sheet of paper and that therocks, boulders, and lumber are in place. The lumberwill be hidden by the rocks above the treasure. (NOTE:See Figure 40-1.) Tell your student that hidden some-where in this deserted courtyard is a treasure chest.

Text, pages 158-62

ObjectiveGiven proper instruction, your student will be able to

do the following:• List inclined planes that he sees at home.

Figure 40-1


• 4 strips of paper.• Home Teacher Packet, pp. 30-31.• Preweighed packages totaling 20 pounds (e.g., four5-pound bags of potatoes).*

• 1 yardstick or ruler.Prepare:

• The lumber and boulders by cutting them from page31 in the Home Teacher Packet.

• The 4 strips of paper by writing one of the followingclues on each strip:

Clue 1Proud and tall we standTo keep the grand surprise.

Clue 2Between us lies a treasureHidden/rom all eyes.

Clue 3Move the rocks and boulders,And you'll be closer to the prize.

Clue 4The planks that stretch across the holeCan be moved if someone tries.

Notes

Reveal the clues. Give your student the piece of paperwith the first clue written on it. (NOTE: During theguessing, discuss each guess, but do not reveal the lo-cation of the chest until Clue 4 has been read and dis-cussed and all guesses have been made.) Tell him toread it aloud. (Proud and tall we stand / To keep thegrand surprise.) Ask him to guess who the we are inthe clue and where the chest might be, according to theclue. (the tree and the flagpole; somewhere near one ofthose)

Give your student Clue 2 to read aloud. (Betweenus lies a treasure / Hidden from all eyes.) Allow him tomake guesses; then let him read Clue 3. (Move the rocksand boulders, / And you'll be closer to the prize.) Askfor more guesses. (NOTE: If he suggests moving therocks at your left of the tree, ask first if those rockscould be the correct ones, according to Clue 2.) (no,because they do not lie between the tree and theflagpole)

With appropriate moans and groans to accompanythe strenuous work that you are doing, "push" the rocksand boulders that your student indicates. Make sure thatyou move all the rocks to a place where they will notblock the opening of the hole where the chest is hidden.You may need to "stack" the rocks near the flagpoleor to the left of the tree. Then give him Clue 4 to read.

This lesson reviews the scientific definition of work(what gets done when a force makes an object movethrough a distance) and the formula for finding out howmuch work is done (amount of force x distance = work),both of which were presented in SCIENCE 3.

This series of lessons may be your student's first ex-perience with alternative solutions to a problem. Take ad-vantage of the drama of the situation, and enthusiasticallypresent each new approach to getting the treasure chest outof the hole!

180 SCIENCE 4 HTE

(The planks that stretch across the hole / Can be movedif someone tries.) Allow your student to pick up the"planks," and stack them against the flagpole. As hemoves the third plank, move aside the cover sheet toreveal the treasure chest in the hole.Conclude the hunt. Point out to your student that nowthat he has found the treasure chest, he has anotherproblem. Ask him to guess what that problem might be.(He must get the chest out of the hole.) Write 20 lb. onthe treasure chest and 5 ft beside the hole. Explain toyour student that the chest weights 20 pounds and thehole is 5 feet deep. Take a few minutes to illustrate theproblem of someone's trying to lift 20 pounds over hishead. On the wall, measure and mark a point 5 feet fromthe floor. Place on the floor the bags weighing 20pounds. Allow your student to see how much weight hecan lift and how high he can lift it.

The treasure chest visual on page 30of the Home Teacher Packet will beused again in Lessons 41 and 42.

Explain that for the next few science lessons, he willbe learning about different ways to do that kind of work.Referring to the scene that is now on the visual (NOTE:See Figure 40-2.), take a few minutes to get your stu-dent's ideas of how he could get the chest out of thehole. At this point, do not discuss the pros and cons ofthe ideas; just let him share ideas leading into the text-book activity that follows.

Figure 40-2


What do you call work? Carrying out the trash? Ridinga bicycle? Reading this page" What qualities must anactivity have for you to think that it is work'!

Scientists define worl. in a way that might surprise you.They say that work is done "hen an object moves througha distance. Would a scientist say then that holding thisbook is work? No. because you are not moving anything. Isriding a bicycle work" Yes. it is. And. yes. so is picking upthe trash can.

158

Teaching the LessonDirect a text activity on pages 158-62. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. How do scientists define work?2. What is the name of a machine that might help you

get the treasure chest out of the hole?Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. How do scientists define work? (Work is done

when an object moves through a distance.)2. Was any work done while you were looking for

the treasure chest? (Yes, moving the rocks andboulders and lifting the lumber involved work be-cause objects were moved through a distance.)

3. What is the name of a machine that might help youto get the treasure chest out of the hole? (an in-clined plane) How would you describe an inclinedplane? (a leaning, or slanted, fiat surface)

4. Look at the treasure chest visual. How could youuse what is there at the scene to make an inclinedplane? (put one of the planks into the hole at aslant)

181

Suppose you wanted to get a treasure chest out of adeep hole, The chest weighs twenty pounds; the hole is fivefeet deep, What arc some ways you could get the chest up?

You could jump down into the hole and try to lift the

chest up, If the chest weighs twenty pounds, how manypounds of force do you think it will take to lift the chestout of the hole? If you said twenty pounds, you are right!To find out how much work you will have to do to lift thechest out, use this formula:

Amount of force X Distance = Work20 pounds X five feet = 100 foot-pounds of work

159

5, Position a "plank" as you have explained, Doesthe plank really solve the problem? Why? (No, thehole is so small that the inclined plane cannot slantenough to be useful.)

6, For an inclined plane to make work easier, it mustincrease the distance that an object will be moved,What can you do to make the inclined plane workeasier? (He could shovel away enough dirt for oneend of the plank to rest at the bottom edge of thechest and the other end of the plank to come to thetop edge of the hole.)

Evaluating the LessonDirect an activity. Ask your student to make a list ofthe inclined planes that are found in his home, You maywant to give him a time limit and send him on an"inclined plane hunt" to different parts of the houseand the yard,

182

You will have to use twenty pounds of force for fivefeel. But suppose you cannot lift twenty pounds over yourhead" You will need to find a way to use less force but stillget the same amount of work done, What will have to bechanged in the formula'!

Let's say that you can lift ten pounds easily, How muchwill the distance have to be to get 100 foot-pounds of workdone with ten pounds of force?

ten pounds x ? ;::100 foot-pounds

You will now need ten feel. How can you increase thedistance the chest has to be moved?

160

EnrichmentSet up an experiment showing how inclined planes

help people do work. Give your student boards of var-ying lengths, a pull spring scale, a stack of books, anda skate or a toy truck. Place the following directionsand questions with the equipment:1. Hook the skate to the spring scale.2. Lift the skate with the spring scale and see how

much force is needed,3. Make an inclined plane with the books and one of

the boards.4, Pull the skate up the inclined plane with the spring

scale and see how much force is needed.5. When was less force needed? Why?6. Try the test with a different board.7. Did you need more or less force this time? Why?

(NOTE: Your student will see that less force is neededto pull the skate up the inclined planes than to lift itstraight up. The longer the plane, the less force will beneeded to pull the skate.)

SCIENCE 4 HTE

Simple MachinesYou can use a machine to move the chest. Maybe you

think only complicated computers, drills, and microwaveovens arc machines. But a stick or a Slone can be amachine. Anything that makes work easier is a machineMachines make our work easier.

Inclined PlanesLook at the picture on this page. This is a simple

machine. Where have you seen such a machine being used')It is an inclined plane. In this phrase, plane means "3 flatsurface." Inclined means "leaning, slanted." How could youuse an inclined plane to lift the treasure chest out of thehole?

Have you ever seen an inclined plane holding a dooropen? What do we call the machine when it being usedthat way'J

161

For Your InformationWith an inclined plane, any increase in distance is

accompanied by a reciprocal decrease in force. There-fore, a treasure chest weighing 20 pounds would require20 pounds of force to be lifted 1 foot. If a 2-foot-Ionginclined plane were used to move the same 20-poundchest a height of 1 foot, pushing or pulling the chest upthe plane would require only 10 pounds of force (dis-regarding friction). If a 4-foot-Iong inclined plane wereused to do the same work, pushing or pulling the chestup the plane would require only 5 pounds of force. Forany inclined plane, the extra distance makes it possibleto apply a force less than the weight of the object beingmoved.

Most archaeologists believe that the ancient Egyp-tians used a system of inclined planes to build the pyr-amids. With thousands of slaves and long inclinedplanes that wound around the structures, huge blocks ofstone could be transported to great heights.


Can you see the inclined planes in these pictures?

162

183

Lesson 41Pulleys,

Wheels, andAxlesText, pages 163-65Notebook, page 48

PreviewObjectives -----


• Identify examples of inclined planes.• Identify examples of pulleys.• Identify examples of wheel-and-axle machines.


• Home Teacher Packet, p. 30.• The paper "planks" used in Lesson 40.• 1 hand mirror.• 1 flashlight.• 1 large empty thread spool.• 1 wire coat hanger.• Wire cutters.*• String.• 1 small pail or a cup with a handle.• 1 crank-type pencil sharpener (optional).*

Prepare:• 1pulley, made with the spool and the wire coat hang-er. (NOTE: See Figure 41-1.)

• A place to hang the pulley. Some suggestions mightbe the shower curtain rod, a doorknob, or a planthook.

If you have easy access to a flagpolewith a pulley, you may want to includethat observing activity as part of yourintroduction to the lesson or as a fol-low-up of the discussion about raisingthe treasure chest with a pulley from aflagpole.

184

Figure 41-1


Conduct a demonstration. Darken the room; then turnon the flashlight and shine its beam onto the floor. Askyour student what path the light travels from the flash-light to the floor. (a straight line) Ask him if he canthink of a way to change the direction of the light. (Hemay suggest putting objects in the path of the light toprevent it from shining onto the floor, but not until hethinks of holding a mirror-or some other reflecting ob-ject-between the flashlight and the floor will he be ableto change the direction of the light.)

After discussing your student's ideas, ask him tohold the mirror so that it redirects the beam of lightfrom the floor to some other spot in the room-againstthe wall or the door. Ask him what the mirror does tothe light. (The mirror changes the direction of the lightand sends it in a straight line to another place.) Askhim to trace the path of the light with his hand, begin-ning at the flashlight, moving in a straight line down tothe mirror, and then moving in a straight line to the spotwhere the light has been redirected.

Turn on the lights and give your student the pulleythat you have made. Ask him whether he recognizes thedevice. (Answers will vary.) Accept his ideas and hisattempts at naming the machine. (a pulley) Ask him toobserve in the following demonstration what the mirrorand the pulley have in common.

Hang the pulley; then give your student the stringand the cup or small pail to try to demonstrate how apulley works. (NOTE: See Figure 41-2.) Ask him whathappens when you pull down. (The object moves up.)Ask him if the pulley reduces the force required to movethe object. (no) A pulley allows a person to pull downrather than to lift. Lead him to conclude that it is usuallyeasier to pull down than it is to lift up. Ask your studentwhat the mirror and the pulley have in common. (Themirror changed the direction of the light. The pulleychanged the direction of the force.)

SCIENCE 4 HTE

PulleysAnother simple machine is a pulley. ;\ pulley is a wheel

with a groove around its outside. A rope passes over thepulley and fits into the groove. When you pull the rope, thepulley turns.

Suppose that the treasure chest is in a hole that is toosmall for an inclined plane to be used. How could a fixedpulley help you get the chest out? How would you set thepulley up?

Sometimes pulleys are used in pairs. One pulley is fixed,and one is hooked to the objeet to be moved. This movablepulley does a different job from the fixed pulley. Itmultiplies force. If you use a movable pulley, you will nothave to use as much force to accomplish the work.

When a pulley is fastened to something that docs nutmove. it is called isfixed pulley. Pulleys change thedirection of force much the way mirrors change thedirection of light.

163

Figure 41-2


164

Teaching the LessonDirect a textbook activity on pages 163-65. Use thefollowing questions to initiate your student's interest inwhat he is going to read.L What type of pulley is our homemade one?2. What is a wheel and axle?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. What kind of pulley is our homemade one? (a fixed

pulley)

Display the treasure chest visual frompage 30 of the Home Teacher Packet.Place the paper planks so that theylook as if they are lying on the groundnear the hole.

2. What simple machine did you learn about in ourlast lesson? (an inclined plane) Was it helpful ingetting the chest out of the hole? (no) Can youthink of another way to get the treasure chest outof the hole, using materials that you see at the site?(Your student may realize that he could remove thepulley from the flagpole and rig it on the tree limb

185

Did you know that a door knob is machinery It is. It isa wheel and axle. In this machine a wheel fixed to ashaft. When the wheel is turned, the shaft turns with it.

Look at any car on the road, and you will see three setsof wheels and axles working. Two sets carry the body of thecar. Where is the third set'? The driver uses it to steer.

Fhis is a windlass. How could you use a windlass tohelp get the treasure chest out'?

165

that stretches over the hole in the ground. He maysuggest using just the rope from the pulley, tossingit up over the limb (which will in itself act as apulley), attaching one end to the chest, and pullingdown on the other end to raise the chest from thehole. If the rope on the flagpole were long enough,he could possibly leave the pulley attached to theflagpole, but this method may cause the rope tofray against the dirt bank of the hole.)

3. How is the movable pulley different from the fixedpulley? (It multiplies force.) What is the advantageof a movable pulley over a fixed pulley? (You willnot have to use as much force to accomplish thework.)

4. What kind of machine has a wheel fixed to a shaft?(a wheel and axle)

5. Can you name one type of wheel and axle men-tioned in your textbook? (a windlass, a doorknob,a steering wheel, the wheels on an automobile)

If you have a crank-type pencil sharp-ener, you may want to show it to yourchild as an example of a windlass. Youmay give him a length of string andask him to demonstrate how the sharp-ener can be used like a windlass to liftsomething up. (See Figure 41-3.)

186

Figure 41-3

6. Look at the picture of the windlass on page 165.How could you use a windlass to help get thetreasure chest out? (You could tie the chest ontothe end of the rope and crank the chest out of thehole.)

SCIENCE 4 HTE

name _

Libel each ctr.wIng .IP (Inclined pl.n.), P (pulley), or WA (wheeland axl.). For Your InformationAlthough the focus in this lesson is on the fixed

pulley and the wheel and axle, the movable pulley ismentioned as a simple machine that multiplies force. Ina single movable pulley, two sections of the rope sup-port the pulley; therefore, only half as much force isnecessary to raise an object.

A block and tackle is a combination of a fixed pulleyand a movable pulley. The fixed pulley, as usual, chang-es the direction of the force, and the movable pulleychanges the amount of the force. Scaffolds for painters,exterior window washers, and billboard poster hangersuse the block and tackle.

187

llMWA --1L

L--.WA. -.WA.. -p-

flI! ~~

.se: -p- -.WA..

.,vuo 80~J6ft•• unlverlltY P" ••. ReprodUcHon ptotllDI1W.o Sdenc:e4 lellon'"~,- Evalu.tJngth,Lanon 48

Evaluating the LessonDirect a notebook activity on page 48. Ask your stu-dent to read the directions at the top of the page; thentell him to complete the page as directed.

EnrichmentGive your student the pulley that you have made

(along with others that you have available), string, scis-sors, pull spring scales that measure grams and ounces,and objects to lift. Prepare a way to attach the pulleysto the wall or in a doorway. Invite your student toexperiment with the pulleys and to measure the forcerequired to lift each object with and without a pulley.


Lesson 42LeversText, pages 166-67


PreviewObjectives


• Identify the fulcrum of a lever.• Identify the load of a lever.• Identify the force of a lever.


• A Write It flip chart.• 1 lever-type can opener.*• 1 empty, clean can.• Home Teacher Packet, p. 30.• The paper "planks" used in Lessons 40 and 41.• 1 pull spring scale.*t• 1 plastic bag.• 1 set of gram weights or standard mass set.*t• 1 wooden ruler.• String.• 1 chair.

Prepare:• A simple sketch of a lever-type can opener on theWrite It flip chart.


Direct a Finding Out activity on textbook page 167and notebook page 49. Ask your student to read theactivity before beginning. Allow him to place the pullspring scale, the plastic bag, the gram weights, thewooden ruler, and the string on a table. He should alsoset the chair in front of the table.

Allow your student to put some of the weights intothe plastic bag and hang it from the pull spring scale,as described in Step 2 of the activity. Tell him to recordthe weight in the correct place on his notebook page.Ask him how much force it takes to lift the bags withthe weights. (It takes as much force as the weight of the

188

About LeversI. Get a spring scale, a plastic bag, gram weights, a

wooden ruler. some string, and a chair.

2. Choose some weights and put them into the bag.Record how much weight is in the bag. Tie the bag toone end of the ruler.

3. Attach the spring scale to the other end of the ruler.Lay the ruler over the chair, using the back as afulcrum.

4. Lift the bag, using the lever. Experiment by moving thefulcrum closer and farther away from the bag beinglifted. When is the bag easiest to lilt' Record yourobservations.

167

bag to lift it straight up without using any type of simplemachine.) Then tell him to remove the bag from thepull spring scale hook and to tie the bag to one end ofthe ruler. Tell him that in this activity the ruler repre-sents the simple machine called a lever. Ask him if heknows what a lever is. (Answers will vary. A lever is abar that turns on a point.) He should continue, as ex-plained in Step 3, to attach the pull spring scale to theother end of the ruler by the ring, secure it with string,and lay the ruler over the top of the chair back. Tellyour student that the chair back is the fulcrum of thelever. Ask him if he knows what a fulcrum is. (Answerswill vary. A fulcrum is the point on which the leverrests.)

Continue the activity by having your student followthe actions described in Step 4. He should slide the rulerover the back of the chair to move the load (the bag)closer to or farther from the fulcrum. Point out that theweight that shows on the scale is the amount of forcethat it takes to lift the bag by using the lever.

SCIENCE 4 HTE

name _

I. The spring scale shows this amount of weight in thebag. _

2. It takes this much effort to lift the bag. _

load fulcrum force

49

LeversProbably the most familiar simple machine is the lever.

Almost any pole, rod. or stick can be a lever. A lever is abar that turns on a point.

1 he point on which the bar rests "the/itfcrum. I hecloser the fulcrum is to the load. the easier it will be tomove the load. Suppose you rigged up a pulley to lift thetreasure chest. But when you jumped into the hole to tie arope around the chest, you found that you could not get therope under the chest. How would a lever help you?

Is this boy using a lever?

166

3. It takes less effort to lift the bag (the load) with thelever.

a. When the fulcrum is inches from theload, it takes this much effort to lift the load.

b. When the fulcrum is inches from theload, it takes this much effort to lift the load.

c. When the fulcrum is inches from theload, it takes this much effort to lift the load.

4. This experiment shows that the closer the fulcrum is tothe load, the (less/ more) effort it takes to lift the load.

01990 80b Janel University Pr",. Reproduction p..onibited


teeson aaTeaching the Lesson

Discuss the activity. Talk with your student about whenthe bag is easiest to lift Lead him to conclude that, witha lever, the closer the fulcrum is to the load, the lessforce it takes to move the load, Instruct him to completehis notebook page,


Teaching the LessonDirect a text activity on page 166. Use the followingquestion to initiate your student's interest in what he isgoing to read: How would a lever help you to move thetreasure chest?Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read,L What is a lever? (a bar that turns on a point)2, What is the fulcrum? (the point on which the lever

rests)

Display page 30 of the Home TeacherPacket showing the treasure chest vi-sual with the planks lying on theground next to the hole,

3, What materials could you use as a lever? (planks)How would the lever help you lift the treasurechest? (It would help you lift the chest up slightlyso that you could tie a rope around the chest.) Tolift the chest, you would have to push down at the"force" end of the lever so that the "load" endwould move upward,

189

name _

Labellhe fulcrum (n thl 100d (L.), and the effort (f) ollach IIVlr bllow.

E FB'7 \\ \\ <;[)L ~L

In each tool below the" If'! two levers Ih.t Ina,. on. fulcrum. In each laver, libel the fufcNm (F), theload (L), and th' 'Hort (E).

E~F L____o<-.-~E L

~

L L

F

LALIE ~

E E

~1990aobJone, University Press. Reproduction prohibited


lesaon42EVllualinglhaltnon

For the following questions your childwill need the can opener, the can, and

. , the prepared sketch on the Write It flipchart.

~-----'4. A can opener is a type of lever. Try putting a hole

in this can with the can opener.5. Look at the sketch of the can opener on the Write

It flip chart. Identify the fulcrum, the load, and theforce. (NOTE: As your student identifies each part,label the sketch on the flip chart. See the sketch onnotebook page 50 pictured in the Home Teacher'sManual.)

6. How is the force required to make the hole in thecan different from the force required to lift thechest with a lever? (To make the hole, he had tolift up on the "force" end so that the "load" endwould move downward. To lift the chest, he had topush down at the "force" end of the lever so thatthe "load" end would move upward.)

190

Evaluating the LessonDirect a notebook activity on page 50. Instruct yourstudent to read the directions for labeling the fulcrum,the load, and the force of each lever pictured on the topof the page. When he has completed labeling the partsof the lever, give the correct labeling. for each lever;then discuss any parts that he had difficulty with. Workthe bottom of the page together. Help your student tosee that each tool is two levers with a common fulcrum.(NOTE: In the picture of the tin shears and the tin, theload has been transferred from the shears to the tin.)

For Your InformationLevers are divided into three classes, depending

upon the positions of the force, the fulcrum, and theload. In the first-class lever the fulcrum is located any-where between the force and the load. That type of lever(a crowbar, scissors, pliers, seesaw, can opener) changesthe direction of a force. The force pushes in one direc-tion, and the load moves in the opposite direction.

In the second-class lever the load is between theforce and the fulcrum. That lever (a wheelbarrow, nut-cracker, bottle opener) does not change the direction ofthe force; so both the force and the load move in thesame direction.

In the third-class lever the force is between the loadand the fulcrum. That lever (a broom, shovel, tweezers,fishing pole), like the second-class lever, does notchange the direction of the force.

SCIENCE 4 HTE

Lesson 43Wedges and

ScrewsText, pages 168-70



Conduct an activity. Give your student a piece of con-struction paper, a ruler, a felt-tip pen, and scissors. Dem-onstrate how he should make a square of the construc-tion paper. (NOTE: See Figure 43-1.) When he hasmade the square, tell him to lay the ruler diagonally onthe paper, on the fold line, then to draw a heavy linewith the felt pen. Tell him to cut along the middle ofthis line, leaving part of the line showing along bothsides of the long edge where he cuts. Ask your studentto look at the two pieces that he has just made and totell what simple machine each piece looks like. (aninclined plane)

Explain to your student that he can use his inclinedplanes to make the shape of the simple machine foundon an ax, a chisel, or a nail. Allow him time to experi-ment by putting his two planes together to form a simplemachine. Tell him that the simple machine he is tryingto make is called a wedge. If he has not figured out howto put the planes together, show him how to put themtogether to form a wedge. (NOTE: See the figure onpage 168 of the student textbook.)


• Complete a paragraph telling what he has learnedabout simple machines.


• 1 sheet (8t" x 11") of construction paper.• Scissors.• 1 ruler.• 1 unsharpened pencil.• 1 felt-tip pen.• 1 roll of cellophane tape.• 1 box decorated like a treasure chest and filled withsnacks to be shared at the end of the lesson(optional).*

Figure 43-1

_---8'1,'-- __

----8'1,'---·

",,-18'/'''

j


About Screws

I. You will need a sheet of construction paper, scissors, afelt marker, a ruler, and an unsharpcncd pencil.

2. Make a square of the paper. Lay the ruler diagonallyon the paper, from one upper corner 10 the oppositebottom corner. Draw a line with the felt marker.

3. Cut along this line. You should have two inclinedplanes now,

4. Hold your pencil upright. Put the shortest side of theinclined plane along the pencil. Now, with the felt-marker line showing, wrap the inclined plane aroundthe pencil.

5. You have made a screw. Turn the pencil around once.How far does the inclined plane rise'! Record yourobservations.

169

Direct a Finding Out activity on textbook page 169.Instruct your student to read the steps in the activity.Then ask him which steps he has already completed.(Steps 1-3)

Give your student an unsharpened pencil and a pieceof cellophane tape. Tell him to follow the directions inStep 4, using one of his inclined planes. Instruct him totape the short side of the inclined plane to the pencilbefore he starts wrapping it around the pencil.

192

Rndlng Out About Screws

name _

React Ind follow the directions below I. you do Step 5 on page 170 In your textbook.

1. Hold the screw on your desk top with the point of theinclined plane facing you like this.

2. Put a finger on the pencil at the point of the inclinedplane and move your finger up the plane as you turnthe pencil one whole turn. Stop turning when the pointof the inclined plane faces you again.

3. On the sketch of the screw model in the margin, write Jwhere your finger was at the end of one turn.

4. Predict how many more complete turns it will take toreach the top of the inclined plane. Write yourprediction here. __

5. Test your prediction. Were you correct? __

Step 1

Step 2

Step 3

~1990BobJonesUniversilyPre" Reproduction prohibited

Telch!ngthel,non 51D LeS8Qo43

Direct the use of notebook page 51. Instruct your stu-dent to follow the instructions on his notebook page ashe does Step 5 of the Finding Out activity. Then discussthe observations, leading your student to conclude thatthe inclined plane rises the distance between two adja-cent threads of the screw for each full turn of thescrewdriver.

SCIENCE 4 HTE

WedgesLet's say that by using one or more simple machines,

you were able to lift the treasure chest out of the hole. Butit is sealed shut. You could wait until you get back to yourhouse to open it. Your curiosity is too great. though. Youwant to open it now. Another simple machine might help.

A wedge is really two small inclined planes put together.Axes, chisels, and even nails are wedges. Sometimes awedge splits an Object, makes holes in it, or chips it.Sometimes a wedge can tilt a heavy object a little off theground.

Can you think of a wedge used at the dinner table? Howmight you use a wedge to get into the treasure chest?

"And the house, \,t'/1£'17 II was ill building, was built ofstonemade readv before it was brought thither: so that there wasneither hammer nor ax nor lIny tool oj iron heard in thehouse, H·hi/p il \t-'fJ\' ;11 huilc/iJJg .. I Kings 6.1

168

Teaching the LessonDirect a text activity on pages 168 and 170. Use thefollowing questions to initiate your student's interest inwhat he is going to read,L What is a wedge?2, What kind of screw could help you get into the

treasure chest?Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read,L What is a wedge? (two small inclined planes put

together)2, How could you use a wedge, perhaps one made of

steel or iron, to open the treasure chest? (Lead himto conclude that a wedge would have to be used incombination with some type of hammer [a lever)with which the wedge could be struck.)

3, What is a screw? (a spiral inclined plane)4, What kind of "screw" could help you get into the

treasure chest? (a drill bit used with an electricdrill)


ScrewsEverybody knows what a screw is. But few may know

that it really is a spiral inclined plane. The screw is notalways driven into wood. Sometimes it lilts things.

An electric drill uses a screw. How" If the treasure chestis really well locked. you may have to wait until you gethome and use the electric drill on it!

170

You may want to open the box thatyou have decorated like a treasurechest and offer some kind of snack foryour child to enjoy before doing theevaluation,

193

Simple Machines

name _

Compte'. thl' paragrlph with Inlormatlon that you have learned about simple machine•.

We are studying simple machines in science class. I'velearned some new things from our lessons. For instance,

I also learned _

Another fact I learned _

However. the most interesting thing I learned was __

CI99(l Bob Jones Un;ver,;ty Pre!! Rep.oductlonprohlblted

Lellon43

Ev.I~lIln"lh'Lt ••onD Sdence4Notebook''''' 52

Evaluating the LessonConduct a writing activity on notebook page 52. Tellyour student to read the notebook page and then com-plete the paragraph with information he has learnedabout simple machines. When he has completed theparagraph, tell him to read his paragraph quietly to him-self and to make any changes that would make theparagraph clearer to a reader.Conclude the activity. Ask your student to read hisparagraph aloud to you. You may want to have him readit to the family at a later time.

194

For Your InformationAlthough a wedge is a form of inclined plane, there

is a difference. With the inclined plane the object movesup the incline, but with the wedge, the incline movesinto or under the object. Examples of the wedge includethe plow, ax, chisel, nail, knife blade, scissors blade,and pin.

The spiral ridge of a screw (which is actually theincline of an inclined plane that winds round and round)is called the thread. The distance that a screw movesinto an object in one complete turn is the same as thedistance from one thread to another. That distance iscalled the pitch of the screw. Besides the wood screw,examples of the screw are found in the cap of a jar orbottle, an adjustable wrench, a clamp, and the base ofan electric light bulb.

SCIENCE 4 HTE

CHAPTER

11Trees

Lessons 44-47

~Trees

171


This chapter, an extension of Chapter 4 (Plants), dis-cusses trees and their classification through the use ofleaves. In Lessons 44-46 your student learns, in hands-onactivities, to classify leaves and to make a leaf collection.At the end of the chapter, he begins a diary of his own"adopted" tree.



* 1 plant press (optional) (Lessons 44-45)* Pictures of poison ivy, poison oak, and poison sumac

(Lesson 44)* 1 ink pad (Lesson 45)* Several leaf key books (available from libraries)

(Lesson 46)* 1 conifer branch and cone (Lesson 46)

195

Lesson 44Identifying

Leaves (Part 1)Text, pages 172-75

PreviewNotes

Objectives

There are several ways to press plant leaves. The mostcommon method is to make a press of two frames of lightslats (1' x 1+') with an inner sandwich of cardboard blot-ters and newspapers. Everything is bound firmly togetherby belt straps. (NOTE: See Figure 44-1.)Given proper instruction, your student will be able to

do the following:• Distinguish between simple and compound leaves.• Distinguish between lobed and unlobed leaves.


• 1 plant press (optional). *• Newspapers or an old telephone book.• Several large, heavy books.• Pictures of poison ivy, poison oak, and poison

sumac.*• 1 paper bag or shoe box.

Figure 44-1

Step 1

196

Step 2 Step 3

SCIENCE 4 HTE

Leaves may also be pressed by carefully laying theleaves flat between newspaper pages or the pages of anold telephone book and then laying heavy books on topof the newspapers or book. A wooden tennis racket withcardboard can also serve as a press. (NOTE: See Figure44-2.) Plant presses are available through biologicalsupply houses, if you choose not to build one.

Figure 44-2

Heavy books

Tennis racketpress with boards

Mesh press


About Leaves

1. Gather ten different kinds of leaves.

2. Decide whether each leaf is simple or compound. Maketwo groups.

3. Tell whether each simple leaf is lobed or not.

175

Lessonlntroducinq the Lesson

As your child observes the differentleaves during the next two lessons,point out the beauty of God's designin the many shapes, shades, and tex-tures of the leaves.

Direct a Finding Out activity on textbook page 175.Take your student outside and have him collect tendifferent kinds of leaves in a bag or shoe box. Be surehe includes at least one conifer branch and cone. Tellhim to collect good specimens so that he can identifythem easily. Tom or damaged leaves are not practicalto classify. Emphasize that he is to collect tree leavesrather than leaves of small plants or bushes. Show yourstudent the pictures of poison ivy, poison oak, and poi-son sumac leaves. Tell him to avoid collecting theseleaves because they are poisonous to touch.

Back inside the house, have your student put asidehis leaves until after the text activity.

197

There arc so many trees in the world that we usually donot even think about them. But imagine what your city oryour neighborhood would look like without any trees at all,Can you think of any trees that you pass on your way toschool" Could you describe any of the trees to someoneelse -or do all trees look alike to you"

You can learn to tell which group a tree belongs to andhow to tell One tree from another in a group, In otherwords, you can learn to classify trees.

172

Teaching the LessonDirect a text activity on pages 172-74. Use the follow-ing questions to initiate your student's interest in whathe is going to read.1. How do scientists classify trees?2. What are simple and compound leaves?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Can you think of any trees that you pass on your

way to church? (Answers will vary.)2. How do monocots and dicots differ from conifers?

(Conifers have seeds in cones; monocots and di-cots have seeds in flowers and fruits.)

3. How do scientists classify trees? (by leaf shapeand size)

4. Look at the pictures on page 173. Point out theconifer leaves and the monocot/dicot leaves. (Thetwo pictures on the left show monocotldicot leaves,and the one on the right shows conifer leaves.)

5. What are simple leaves? (leaves that are not divid-ed into separate parts.) What are compoundleaves? (leaves that have separate parts) Simpleleaves have a more defined stem than the com-pound leaves.

198

A tree is a fall plant with one long stem, Trees rnav bemonocots, dicots, or conifers. Do you remember how themonocots and the dicors are different from the conifers')Conifers have seeds in cones; monocots and dicots have

seeds flowers and fruits.

Classifying by LeafYou can classify trees by leaf shape and Be sure to

look at the leaves carefully, observe the details, and noticethe differences,

Do you remember what conifer leaves look like? If youdo not, be sure to check that section of the book againbefore you start to classify

173

6. Look at the pictures on page 174. Which leavesare simple and which are compound? (The twopictures on the left show simple leaves, and theone on the right shows compound leaves.)

7. Simple leaves may have lobed edges. What arelobed edges? (parts that stick out like knobs orpeaks) Which leaf on page 174 has lobed edges?(the one in the bottom picture)

Evaluating the LessonComplete the Finding Out activity on textbook page175. Tell your student to take the leaves he collectedearlier and to place them into two groups-simple andcompound. (NOTE: Conifer branches and cones shouldbe placed in a third pile.) Once he has done this, askhim to look at his stack of simple leaves and to decidewhich are lobed and which are unlobed.

Check your student's sorting work. Tell him to savehis leaves for the next lesson by carefully laying themflat between sheets of newspaper or the pages of an oldtelephone book. If a plant press is unavailable, large,heavy books should be laid on top of the newspapers topress the leaves and conifer branches and cones.

SCIENCE 4 HTE

Simple and Compound LeavesMonocot and dicot leaves ean be put in one of two

groups: simple leaves and compound leaves. Leaves that arcnot divided into separate pans me simple leaves. Simpleleaves may have lobed edges pans that stick out likeknobs or peaks. Lobes can be rounded or pointed. Can youfind the lobed leaf below')

Compound leaves have separate parts, not merely lobes.Each separate part is called a leaflet. Look at the pictures ofleaves on this page. Which leaves arc simple? Which arecompound? How are they different?

174

If possible, try to save your child'sleaves as he has sorted them. This willsave time during Lesson 46.

For Your InformationLeaves come in a variety of sizes and shapes. It is

sometimes difficult to tell the differences between asimple leaf and a leaflet of a compound leaf. Two cri-teria are used to distinguish leaflets from simple leaves.First, buds are found in the axils (point where the leafjoins the stem) of simple and compound leaves but notin the axils of leaflets. Second, leaves grow out from astem in all planes, whereas leaflets of a compound leafall lie in one plane.



Leaves (Part 2)Text, pages 176-77Notebook, page 53



• Distinguish between palmately compound leaves andpinnately compound leaves.

Materials

Poster paints can be used instead of anink pad. These leaf prints can be usedto decorate stationery, place mats, orother paper items.

Have available:• Student leaf collection from Lesson 44.• 1 plant press (optional). *• Newspapers or old telephone book.• Several large, heavy books.• 1 ink pad."• White or light-colored construction paper.• Several interesting leaves.

Direct a leaf print activity. Provide several interestingleaves, an ink pad, newspaper, and white or light-colored construction paper for your student. Guide himthrough the following directions in making a leaf print.

1. Place the vein side of the leaf on the ink pad.2. Lay a sheet of scrap paper over the leaf and rub

the leaf gently to distribute the ink evenly.3. Carefully pick up the leaf and lay the inked side

on a clean sheet of paper.4. Place another sheet of scrap paper over the leaf

and rub the paper gently to make a clear print ofthe leaf on the paper.

5. Carefully remove the scrap paper and leaf.

Ask your student to identify his leaf print as a simpleor compound leaf. If it is a simple leaf, does it havelobed edges? Tell him that today he will learn abouttwo kinds of compound leaves.

200 SCIENCE 4 HTE

Pinnate and PalmateThere are two kinds of compound leaves -pinnately

compound and palmately compound. Pinnate comes froma Latin word, pinna. meaning "feather." Look at thispinnately compound leaf. How do you think this kind ofleaf got its name?

J\ palmately compound leaf has all its leaflets attachedat the same point at the top of the leaf stem. It is similar tothe way your fingers are attached to your hand.

176

Teaching the Lesson

The last paragraph on textbook page177 will be discussed in Lesson 46.

Direct a text activity on pages 176 and 177. Use thefollowing question to initiate your student's interest inwhat he is going to read: What are the two kinds ofcompound leaves?


Of all t he compound leave. in the pict ure, which arepalmate and which are pinnate" What do you think theLatin word palma means')

Plants are classified or identified with a classificationkey. A classification key is made up of paired statements.Choose the statement from each pair that describes the leafyou are studying. Follow the directions at the end of thestatement you choose. Keep reading pairs of statement, andfollowing directions until you find the name of your leaf.

177

201

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Name two kinds of compound leaves. (pinnately

compound and palmately compound)2. Look at the pictures on page 176. Which leaf is a

pinnately compound leaf? (top picture) Which leafis a palmately compound leaf? (bottom picture)

3. Which leaflooks most like a feather? (the pinnatelycompound leaf) Which leaf looks like the palm ofyour hand? (the palmately compound leaf)

4. Look at the pictures on page 177. Which are pal-mate and which are pinnate? (The plant in the topleft picture is palmate, and the other two arepinnate.)

name _

Count the number of each type of ,•• , In your collection. Color In the correct number of bon. In uchcolumn to complete the graph.

10

G 7j r-----~-------+------_+------~'a 6j r-----~-------+------_+------~§ 5z r-----~-------+------_+------~

lobed not lobed pinnately compound p.lmately compou.nd

Write the type of teaf In each blank.

I. The longest leaf is _

2. The widest leaf is _

3. The compound leaf with the most leaflets is _

~1990BOb Jones Universily Press AeplOduction prohibIted

D Sdenc:e4Notebook Packet

Lesson 45

Evalualinglhelenon

Evaluating the LessonDirect a notebook activity on page 53. Ask your stu-dent to read the directions. Instruct him to complete thegraph using the leaves he has collected. Then have himcomplete the remainder of the page.

EnrichmentTell your student that in his lifetime he will use

approximately 70 tons of wood products for furniture,heating, paper, and many other things. Also, tell himthat one mature red pine can produce 450 pounds ofoxygen each growing season. This oxygen will keep aman breathing for a whole year. Allow him to make achart showing the following statistics:1. How many tons of wood products will be used by

all of his family during their lifetime.2. How many pounds of wood products this would

be.3. How many trees it would take to produce enough

oxygen for his family for one year.4. How many pounds of oxygen this would be.

202

53

SCIENCE 4 HTE


TreesText, pages 178-80 and 182

Notebook, page 54

PreviewObjective


• Use a classification key to identify trees.


• Student leaf collection from previous lesson.• 1 conifer branch and cone.*• Several leaf key books (available from libraries).*

You will want to have several leaf keybooks available for your child. Generalbotany textbook lab manuals usuallycontain excellent leaf keys. Try toavoid using "picture" keys having nowritten statements about the trees.Your child needs to learn how to readthrough a classification key in a logicalmanner. One book you may find help-ful is The Audubon Society FieldGuide to North American Trees by El-bert L. Little.


Conduct a Finding Out activity on textbook page 182and notebook page 54. Before beginning this activity,allow your student to retrieve his pressed leaves fromthe newspapers. Tell him to handle the leaves carefully.He will be using his leaves during the lesson and mustnot damage them. Explain that he will work to key all


About Trees

I Get a small twig and a cone from an evergreen tree.

2. Using the key. try to (ell what kind of conifer it is.


182

ten of the leaves that he has collected. (NOTE: Thenumber of leaves may be reduced if lesson time islimited.)

Call attention to the classification key beginning onpage 178. Instruct him to select the conifer branch andcone from his collection. Demonstrate the key using theconifer branch and cone. Answer any questions thatyour student may have. Remind him to take his timeand to examine the specimens carefully and thoroughly.Instruct him to write the name of his specimen and thekey numbers he used to identify the specimen on thenotebook page.

This Finding Out activity will requireyour child to work only through thefirst eight statements of the key. It isimportant that he understands this partof the lesson before going on.

203

name _

Record your finding. here.

Conifer branch and cone: Used key numbers _Leaf name: _

Leaf 2: Used key numbers _Leaf name: _



Leaf 5: Used key numbers _Leafname: _


.

.

.

~

\~Leaf 7: Used key numbers _

Leaf name: _




01990 Bob Jones University Pre». Reproduclion prohibited


lesson 46TeachingthtoLesson

Teaching the LessonComplete the classifying activity. Allow your studentto classify his remaining leaves using the key in thestudent textbook. Once he has discovered the name ofa leaf, he should record his findings on the notebookpage and on a separate piece of paper. Each piece ofpaper can then be placed behind its leaf so that yourstudent can later remember the name of the leaf. Heshould continue the activity until all the leaves in hiscollection have been classified.

Tell your student that he may find a leaf that is notspecifically mentioned in the key. Call attention to theother classification keys you have collected, and allowhim to use them to classify those leaves.

Evaluating the LessonDirect your student in completing his leaf collection.Give him several days to complete the leaf collection.Tell him to mount his pressed leaves neatly on white,unlined paper and to label each piece of paper with theleaf's common name. (NOTE: Allow a little flexibilityhere. The goal is neatness and accuracy, not quantity.)

You may find a photo album an easyway to mount and display your child'sleaf collection.

204

54

A Simple Classification Key to Trees

gQto2.

10. Leaves broad and Hat

8b clusters of five _ White pine

178

For Your InformationThe following terms are used by foresters when

talking about trees.canopy-the cover formed by the grouping of treecrowns at approximately the same height.

live crown-the branch part of the tree which hasliving leaves capable of carrying on photosynthesis.

cull-a tree that does not, nor will ever, have com-mercial value.

den tree-a tree with one or more cavities that areused by wildlife for dens or nests.

mast-any fruit or nut produced by a tree or shrub andproviding food for wildlife.

natural resource-anything used by people that is nat-urally present in the environment. These resourcesmay be renewable or nonrenewable.

stand-a group of trees of approximately the sameage, composition, and appearance. A stand is partof a forest or woodlot.

watershed-an area of land that drains or sheds waterto the same point. This area can be less than oneacre or can cover millions of acres as the MississippiRiver Basin does.

woodlot-a small forest.

SCIENCE 4 HTE

sa Leaves simple

9b. Leaves compound

lOa. Leaves more round than long

10b. Leaves more long than round

11a. Leaves with pointed edges

11b. Leaf edges smooth, leaf fan-shaped Ginkgo

128. Leaves with five distinct lobes., not fuzzy on bottom of leaf Sweet gum

12b. Leaves without five distinct lobes go to 13.

13a. Leaves light green on top, fuzzy white below. 3-5 lobes __ Sycamore

13b Leaves with several painted lobes (more than five) Maples

14a. Leaves lobed

14b. Leaves not lobed

go to 10.

90t021.

go to 11.

901014.

goto 12.

go to 15.

15a Leaves dark green above. light green below, the lobes ending in ~~

~ __ !a£pO~i~nt~==============================~B~la~Ck~o~a~k~~

go to 17.

1_'6_a_.~Le~a~ve~S~W~il~h~'h~r~e.=I=ob=e=s=.s=0=m=et='m=.=s=o=n=.=or=t=w=o.=v=e~==S=Pi=CY=$=m=e~lI~in~g~~~~l- when crushed Sassafras if!F~'6~b~.~L.~a~v.~s~W~H~h~m~a~ny~m~or~.~th~a~n~th~r~.e~t~Ob~.~S-===========~W~h~ite~O~a~k~QP~

15{), Leaves light green, lobes are rounded

179


go to 16,

~~17~a~.L~e~av~e=S~la~~~.~.d~a~rk~g~r~ee~n:.~sh~in~Y~.a~n~d~~~i~Ck~===========:M~a~gn~o~li~a~

17b, Leaves thin, not shiny go to 18.

~ll~~~~~~~~=W~.IIOW~7'" ~. Leaves 3-4 times longer than width, leaves narrow

18b, leaves 2 times longer than width goto 19.

19a, Leaf edges with tiny teeth go to 20,

~~ 20a, Leaf tubes easily seen on leaf surface and evenly spaced. dark

~~ __ g~r~ee~n~o~n~t~oP~==============================~E~lm~»~

19b, Leaf edges smQoth Dogwood

2Ob, Leaf tubes not easily seen Cherry

21a, Leaves palmately compound Buckeye

21b. Leaves pinnately compound go to 22.

223 leaves twice pinnately compound go to 23,

22b, Leaves once pinnately compound go to 24.~~,.,,,,\\~ ~2~~~Tr~u~nk~0~1~lr~e~e~ha~$~la~r~ge~t~h~or~n~s~==============~H=o:n~eY~L~oc~US:t~

~ 23b, Trunk of tree has no thorns Mimosa~~~~==~~'~lil:'24a. Leaflets very long and narrow Palm

~I~~~~~~============~~~~"f -'ll ~4b. Leaflets egg-shaped Black Locust

180

205

Lesson 47Adopt-a- Tree

Text, page 181Notebook, pages 55-56

PreviewObjective


• List the basic characteristics of a tree as determinedby observation.


• 1 tree.

NotesRather than having your student "adopt" an existing

tree, you may want to plant a tree in your yard. Contactyour local Cooperative Extension Service, State Forester,or nurseryman. These people can help you choose a treethat would grow well in your area and specific site. Theyalso can give you correct planting instructions and specificinformation about proper care after planting. The NationalArbor Day Foundation in Garnerville, NY 10923 is also agood source to contact.

Allow your student to examine the seedling before itis planted. Ask him to name one unique thing that henotices about the tree. Discuss the importance of parts suchas roots, root hairs, stems, needles, etc.


Direct a discussion. Tell your student that he will be"adopting" a tree near his house or in his yard. Askhim what the word adopt means. (to choose and takeinto one's own family) Tell him that this is what Goddoes to us when we believe in His Son, Jesus Christ.(Bible Promise: H. God as Father)

206

name _

My Adopted Tree Diary(First Visit)

Nameoftree: _

Drawing of tree:

Location: _

Size: _

Leaf shape, bark color, etc.: _

Sounds: _

Smells: _

Visitors: _

Shadows: _

Neighbors: _

°l990BobJonesUnlvellltyp, ••• ,R.producUonprohlbllfld.

D Sdence4Notebook PacMt

Leeson 47

T,.ctllnglheL'Sion 55

Direct a notebook activity on pages 55-56. Tell yourstudent that he will also be keeping a diary about hisadopted tree for the remainder of his fourth grade year.Tell him that today he will make his first observationof his tree. There will be repeated visits during the restof the year to compare observations made each time.

SCIENCE 4 HTE

name _

My Adopted TreeDiary(Repeat Visits)

Name of tree: _

Size: _

Leaf shape, bark color, etc.: _

Sounds: _

Smells: _

Visitors: _

Shadows: _

Neighbors: _

~'990 Bob Jones University P'M'. Reproduction prollibiled

D Sdence4Nolebook Packet

Lesson 47Teaching lhe \.-..on S6

"For ye shall go out H"iIIl ivy. aile! he Ice/forth Hill! peace:the mountains and the hills shall break forth he/ore rOll

into singing. and all the trees of IIIf' field shall clap theirhands. Instead 0/ the thorn shall ,WI/(' lip thefir tree, andinstead of lite brier shall ('omt' up the myrtle tree: and if

shall he to the Lordfor a name . for an everlasting sign thatshall not be cut ofI .. I.'tlft/It j5:i2-/J

181

Take your student outside, and have him select aliving tree to adopt. For this first visit (use notebookpage 55), instruct him to describe the tree as it is today.Use the following questions to help your student beginhis description.

How can you tell that the tree is alive?Listen to see whether the tree makes any sounds.Does the tree make any sounds?What kind of odors are there?Do different parts of the tree have different odors at

other times of the year?What might the tree look like the next time you visit

it?What animals (insects, birds, mammals) might visit

the tree?Why do you think these animals would visit the tree?What must the tree have to survive?How old do you think the tree is?What kind of shadow does the tree cast?

When your student visits his adopted tree, forewarnhim that he is not to taste any part of the tree.


Teaching the LessonDirect a text activity on page 181. Use the followingquestion to initiate your student's interest in what he isgoing to read: How is the tree described like a person?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Read Isaiah 55:12-13 aloud from your Bible.2. Do you know what personification is? (Answers

will vary. It is thinking of or representing an in-animate object as having personality or the qual-ities, thoughts, or movements of a human being.)In what expressions does the writer of these versesuse personification? (the hills singing and the treesclapping their hands)

3. Do you think the word ye in these verses refers toa saved person or to an unsaved person? (Answerswill vary. It must refer to the saved because of thewords joy and peace.)

207

If your child is having difficulty un-derstanding these verses, you maywish to explain that during the Millen-nium the effects of sin will be reversedon the earth. Not only will everyonehave inner joy and peace because ofsalvation, but there will also be chang-es in the physical creation. Adam's sinbrought thorns and thistles; the Millen-nium will replace those with differentkinds of growing things. The people'sjoy in the changes in nature will makeit seem as if even nature is joyful. Allof these changes will indicate that Godis in control and sin has been con-quered. (Bible Promise: E. Christ asSacrifice)

Evaluating the LessonDirect an activity. Give your student a sheet of paper.Ask him to draw a picture of his adopted tree and writea paragraph describing his tree. Encourage him to invitea friend or family member to visit his tree. (NOTE:Remind your student to keep up with his adopted treediary. Try to set a time each week until the end of thefourth grade year for your student to observe his adoptedtree and to make entries in his diary.)

You may choose to allow your childto take a picture of his "adopted" treerather than to have him draw a pictureof it. He could continue to take pic-tures of his tree as he completes hisdiary.

For Your InformationArbor Day started in 1872 in Nebraska. J. Sterling

Morton, a long-time conservationist, introduced a res-olution to the Nebraska State Board of Agriculture nam-ing August 10, 1872, "Arbor Day" in Nebraska: a day"especially set apart and consecrated for tree planting."Shortly after this observance, several other states passedsimilar legislation, and began observing Arbor Day,sometimes on dates other than August 10. By 1920morethan 45 states were celebrating Arbor Day. Traditionallypeople plant trees to commemorate Arbor Day.

208 SCIENCE 4 HTE

CHAPTER

12How Earth's Crust

Wears Down

Lessons 48-51

III How Earth's CrustWears Down

183


This chapter introduces mechanical and chemicalweathering, the processes that break down rocks into soil.The ways that soil can be lost, mass-wasting and erosion,are also presented. Emphasis is placed on the Christian'sstewardship responsibility to God's creation. Many hands-on activities throughout the chapter aid your student inunderstanding the different processes at work on and underthe earth's surface.



* Several small pieces of limestone (Lesson 48)* 1 large apple (Family Time 49)* 1 small piece of carpet (Lesson 49)* 1 small piece of tile or linoleum (Lesson 49)* Fine potting soil (Lesson 50)* 2 large measuring beakers+ (Lesson 51)

209

Have available:• 1 small glass jar.• Water.

210

TEACHER'S EDITION

FamilyTime 48Finding OutAbout Frozen

WaterMaterials ------ Instructions ------

Guide your child in an activity. Allow him to fill theglass jar to the brim with water and cap it tightly. Placethe jar in the freezer the day before teaching Lesson 48.(NOTE: You may want to put the jar on a pan to catchthe broken glass.)

Ask your child the following questions to initiateinterest in the activity for tomorrow's lesson.

1. What do you think will happen to the water?2. What will happen to the glass jar?3. How do you think frozen water might affect rocks?

SCIENCE 4 HTE

Lesson 48

Objectives

thinks that the word weathering refers to. (slowchanges)Continue with another activity. Place several piecesof limestone into the empty cake pan; then ask yourstudent to add his pieces to the pan. Add enough vinegarto cover the bottom of the pan. Heat the pan on thestove.

As the pieces of stone are heating, display the frozenglass jar. Ask your student what has happened to the jarand what has caused it to happen. (The jar is crackedor broken because water expands when it freezes.) Askhim how frozen water could break down rock. (Waterseeps into the cracks of rocks and then expands whenit freezes.)

Allow your student to observe the effects of theheated vinegar on the limestone. Bubbles should beforming on the pieces of stone. These bubbles are theresult of the chemical change caused by the acid in thevinegar. If the process were continued, the limestonewould eventually break down completely.

WeatheringText, pages 184-88Notebook, page 57

Preview


• Identify methods of mechanical weathering andchemical weathering.

• Identify parts of the soil.


• Several small pieces of limestone. *• I piece of paper.• I cake pan.• Vinegar.• I small glass jar prepared in Family Time 48.

Pieces of building brick or concrete

~. ~ ,--_m_a_y_b_e_s_u_b_st_it_u_te_d_fo_r_li_m_e_s_to_n_e_fo_r-.Juse in the weathering activity.


Direct an activity. Explain to your student that in to-day's lesson he will learn about weathering. Tell himthat he will do activities to see what changes affectrocks. Give him two small pieces of limestone and apiece of paper. Direct him to rub the pieces togetherand to note how long it takes to rub off a few smallparticles of stone. Ask your student to try to think ofnatural changes that would break off small bits of thelimestone similar to what he has done. (Answers willvary.) Ask him how wind and sand might change thelimestone. (The sand wears away at the limestone. Thewind carries the sand away to wear at other rocks.)Direct a discussion, encouraging him to use his findingsto predict how long it might take wind and sand to wearaway an equal amount of stone. After discussing howlong it takes the wind and sand to wear away at thelimestone, ask your student what kind of changes he


"And surely the mountain falling cometh 10 nought, andthe rock is removed out of his place. The waters wear thestones: thou washest a~t'{I)' the things which grm1' out of thedust ofthe earth." Job 14:18-19

If you took a walk through southern England. youmight imagine that you were walking where Alfred theGreat had ridden his horses. waged his battles. and ruledhis people more than a thousand years ago. In a way that istrue. Hut in another way. you could never really walk thesame hills or till the same soil that the Saxons did.

Every day wind and water change the surface or theearth. They move sand, break down rocks, wear awaymountains, and carry tons of soil from one place toanother. Most of thc changes are slow and gradual. Someblocks of granite in Egypt have been wearing down formore than 3.000 years. But sometimes the changes are swiftand devastating, A whole town in Quebec, Canada, oncedisappeared in a landslide in less than two hours.

184

Teaching the Lesson

Instruct your child to read through thetop paragraph on page 188. The re-mainder of the page will be read in thenext lesson.

Direct a text activity on pages 184-88. Use the follow-ing questions to initiate your student's interest in whathe is going to read.

1. What is mechanical weathering?2, What is chemical weathering?3. What is bedrock?


1, What is weathering? (breaking down of the rocksinto soil)

2. What is mechanical weathering? (wind,frost, fire,water, or roots acting on and changing a rock)

3. What is chemical weathering? (Gases like carbondioxide mix with water and cause the breakdownof rocks.)

212

WeatheringROl;k~ tan he broken down into smaller piccev hy

weathering, Although that term ma) sound as though \Jnl~

weather change, the rocks. plants and acids can alsoweather stone.

Mechanical weatherirn; happens "hen wind. trost. fire.water, or roots act on a rock and the rock changes. Forexample. wind carrying sand can etch a\\ay at a stonequickly, scouring off hits that then 11, along to weatherother stones.

Frost breaks up rods. Do you know "hat water doeswhen it freezes? It expands. 1f water seep- into the pores UJ

the cracks in rock, what will happen \I hen the temperaturedrops below freezing? Sometimes water that ha!-. rununderground freezes. When it expands. it pushc-, up thesurface and small rocks come to the top. 'I hen a tha«comes, and soil lall-, under the rock-, and hold, them on thesurface. There weather ing "ill work. on the rocks. tOI ruingmore soil.

Running water can wear stone do« n a~ well. 110\\ arcstones in creeks and on beaches different from sioncs infields and along roadbeds?

4. What part of our beginning activity was an exam-ple of chemical weathering? (the vinegar and thelimestone)

5, Look at the cross section of soil on page 187. Whatis the dead plant material found above the topsoilcalled? (humus) The humus provides water andfood for the plants,

6. Which part contains the rich soil that produceshealthy plants? (topsoil) This part has been weath-ered by wind and ice.

7. Which part does not contain humus? (subsoil) Thesubsoil is coarser than the topsoil.

8. Which part is solid rock? (bedrock)9. Do you think the weathering processes are helpful

or harmful? (Answers will vary.)

SCIENCE 4 HTE

185

Plants can break up rocks. Ho\V is it possible that a frailflower or a tiny seedling tree could split a rock? Roots ofplants can push into it small crack in a rock and spread out.As the plant grows. its root-, and stem push with steadyforce against the rock. After a while a small plant Canexpand enough to break a boulder. A plant can grow eventhrough a city sidewalk because the power of its growthforces the cement to give way.

l-orest fire, heat up rocks in a way that the sun doc,not. A fire rushing over a rock call make the outer layerexpand and split off. If the rock is surrounded hy fire longenough, it can actually break apart from the heat.

186


When gases like carbon dioxide mix with water,chemical weathering can happen. Raindrops pick up smallamounts of carbon dioxide from the air. Water and carbondioxide make a weak acid, called carbonic acid. This aciddoes not hurt plants or animals. but it can changelimestone, dissolving it gradually. How might a miner or ascientist use this information to identify limestone?

Weathering decays the earth's crust, breaking it downinto simpler clements. Eventually rocks and bouldersbecome particles, Mixed with dead plant material. calledhumus, soil can hold water and grow new plants.

The rich soil at the surface is called topsoil. The soil justunder that has no humus; it is called subsoil. Why do youthink subsoil is coarser than topsoil? Below the subsoil isbedrock, solid, unweathered rock.

IjtoPsOil

~"".:::.;

1;bedrock

187

213

name _

L_ NOhport of tht I0Il.Drew • line to match the st.tement with the loll part or part, It describes.

humus

lapsoU

rich soil that produceshealthy plants

subsoUby wind

bedrock

"'1990 Bob Jones U,"IIvcrSOlyP'ess AeproduCllonproh.b,red

O Sdence4NoeeIIook , ••••••

Lesson 48

EViltallng III. lI ••on 57

Evaluating the LessonDirect a notebook activity on page 57. Ask your stu-dent to read the directions at the top of the page; thentell him to complete the page as directed.Direct an outdoor observation. Take your student ona walk or drive through the neighborhood looking forsigns of weathering. When you see holes or cracks inthe surface of the road, you might ask him if these werecaused by heavy trucks using the road. (No, roads aredesigned not to crack when supporting heavy trucks andcars.) Ask him what could have caused the holes andcracks. (Freezing water will crack concrete just as itcracked the jar in the demonstration.) Explain to yourstudent that unlike water, rocks contract when they arecooled and expand when they are heated. Ask him topredict how this contraction and expansion will workwith the contraction and expansion of the water to fur-ther speed the weathering of rocks.

Guide your student as he looks for other signs ofweathering. He might see stones worn down from run-ning water or tree roots breaking up sidewalks or roads.If you plan to do the following Enrichment activity, youmay wish to collect your soil samples at this time.

214

EnrichmentCollect, or allow your student to collect, several soil

samples from various places such as a garden, an emptylot, and a wooded area. Remove any large rocks andtrash from the samples and crumble the lumps of dirt.

Fill a separate quart jar for each soil sample one-quarter full with soil. Add a tablespoon of alum to eachjar and enough water to fill the jar to three-quarters full.Label the jar with the place from which the soil came.Cap each jar tightly. (NOTE: See Figure 48-1.)

Place the following directions and questions withthe jars:

1. Shake each jar vigorously for one minute.2. Let the jar stand for several minutes. The soil will sep-

arate into layers of rock and coarse sand, silt, and clay.Any organic matter will float on the top of the water.

3. Study the contents of each jar and answer the followingquestions:

How long did it take for all the particles to settle?Did it take longer for all the particles to settle insome soil samples? If so, which ones? What doyou think caused this difference in settling times?

Why do you think it takes longer for the clay par-ticles to settle?

Which sample has the most organic matter?Which soil would be best for growing plants?How could the soils with little organic matter beimproved?

Figure 48·1

SCIENCE 4 HTE

For Your InformationScientists have identified about seventy thousand

different types of soil in the United States. The soil typeis determined by the type of organic matter present, theclimate, and the type of rocks from which the soil isformed. Characteristics that distinguish soils include theamount of nutrients present, permeability, potential forerosion, color, and texture. The physical characteristicsof color and texture are the easiest to observe.


FamilyTime 49

The Earth andIts Land

Materials InstructionsHave available:

• 1 large apple.*• 1 paring knife.

216

Direct a demonstration. Display the apple and tell yourchild that it represents the earth. Cut the apple into fourequal parts. Tell him that three of these parts representthe parts of the earth that are covered by water. Thefourth part represents dry land.

Cut the fourth land section in half lengthwise. Tellyour child that one of these sections represents areas ofthe earth such as swamps, mountainous regions, deserts,and the Arctic and Antarctic. The other one-eighth sec-tion represents the land where man can live.

Cut this one-eighth piece crosswise into four equalparts. Tell your child that three of these pieces representareas of the earth where the weather is too wet or toohot, or the soil is too rocky or not fertile, or the land iscovered by homes, businesses, or roads.

Peel the last small one-thirty-second ( 3~) section ofthe apple. Tell your child that this small bit of peelingrepresents the soil that we depend on to provide foodfor the whole world!

Obviously, crops will not grow well in rocky soil,nor is it a good idea to build houses on soil that tendsto hold water on the surface. Careful planning to matchthe soil with the land use will help to prevent the lossof this small amount of usable soil.

The following demonstration may beused as an object lesson after readingabout the creation (Genesis 1:1-2:24)or the story of the sower (Matthew13:1-23; Mark 4:1-20).

SCIENCE 4 HTE

Lesson 49

Introducing the Lesson

caused the blocks, as well as the soil and rocks in theseexamples, to fall. (gravity)Continue with another activity. Allow your student toadd a few drops of food coloring to the water. Place thetile on a flat surface. Ask your student to hold the waterdropper about twelve inches from the tile, and allow adrop of water to fall on the tile. Tell him to watch thedrop as it hits the tile. Ask him to describe how thewater splashed. Repeat the same procedure, using thepiece of carpet. Ask him the following questions.1. How is this splash different from the splash on the

tile? (The splash is absorbed in the carpet. Itspreads out on the tile.)

2. Why do you think it is different?3. Which is more like a field covered with grass-the

carpet or the tile? (carpet)4. Which is more like bare soil-the carpet or the tile?

(tile)5. What do you think the drop of water represents?

(raindrops)6. Is rain more harmful to bare soil or soil covered

with grass? (It is more harmful to bare soil becauserain moves bits of dirt on the bare soil.)

Prop an end of the piece of tile and the piece ofcarpet on a wooden block. Allow your student to holdthe dropper twelve inches above each piece and allowa drop to fall. Ask him the folluwing questions.1. What happens to the drop on the tile? (The water

ran down the slope.)2. What would happen to rain on bare soil? (The rain

would run downhill taking some soil with it.)3. What happens to the drop on the carpet? (The water

is absorbed.)4. What does this activity show you about bare soil

and soil covered with grass? (Your student shouldconclude that rain does more harm to bare soilthan to soil covered with grass. It is more harmfulstill to bare, sloped ground because the rain runsoff more quickly, taking more soil with it.)

Mass- wastingand Erosion

Text, pages 188-91

PreviewObjectives


• Find evidence of mass-wasting and erosion in hisneighborhood.

• Describe the problem of mass-wasting or erosion.


• 15-20 small wooden blocks.• 1 small piece of carpet.*• 1 small piece of tile or linoleum.*• 1 water dropper.• 1 cup or bowl of water.• Food coloring.• Paper towels.• Home Teacher Packet, pp. 32-33.

Lesson

Direct an activity. Tell your student that he will bedoing activities today to show examples of two waystopsoil can be lost. Ask him to build a pyramid usingthe wooden blocks. Tell him that the pyramid representsa hill or mountain. Ask him to remove one of the blocksfrom the outside of the bottom level. Ask him what hethinks removing a block represents. (Answers will vary.Removing the block will cause a reaction that representsa landslide.) What happens to the topsoil during a land-slide? (The rock and soil slide downhill.] Why do youthink landslides occur? (Answers will vary. Landslidesusually occur because of the natural instability of anarea, but they can be caused indirectly in places byman.) Can you think of an example of a landslide beingindirectly caused by man? (An example would be whereroads and highways have been cut improperly into thesides of mountains.) Ask your student to tell what force


Mechanical and chemical weathering are constantlyproducing new soil. What would happen to farmlandwithout weathering" Why do you think farmers find newrocks in the fields when they plow each year'!

Mass-wastingWhen large amounts of earth or rock slide downhill. wc

say the earth's crust is changed by maSS-HY15Iillg. Mass-wasting can be slow or terrifyingly fast. But it always makesa big change in the surface of the earth.

One kind of slow mass-wasting is called creep.Sometimes soil slides downhill so slowly that we cannot seeor feel it moving. Even the grass is not disturbed. But byand by we can see the clues of slow mass-wasting.Telephone poles tilt; fences lean; trees grow up in a curve.Why is it important for a house on a hill to have afoundation On bedrock')

188


1. What is mass-wasting?2. What is erosion?

Continue with discussion questions. After your stu-dent completes his silent reading, use .the followingquestions and statements as a guide to discuss the pageshe read.

1. What is mass-wasting? (the earth's crust beingchanged by large amounts of earth or rock slidingdownhill)

2. Look at the picture on page 188. What probablycaused these trees to tilt? (soil creep) How mightsoil creep affect other things, such as buildings,roadways, and bridges? (Answers will vary.)

3. Why is it important for a house on a hill to have afoundation on bedrock? (Soil will slowly slidedownhill, but bedrock is solid.) This principle ap-plies to our lives as well. We must build our liveson the Rock, the Lord Jesus Christ. (BAT: la Un-derstanding Jesus Christ)

4. What is erosion? (the carrying of soil from oneplace to another)

218

When mas •..-wasting i.., swift, it is much more dangerous.A lantlstid« is a sudden downhill movement of rod: or soil.If the slide is made partly of ice or S"O", it is an avalanche,

In J8B!. it town in Swir/crlund was mining themountain nearby. The miners worked so lar into themountain that a crack broke upward into the top, Rocksbegan to fall night and day. and a huge piece 01 themountain began to creep down toward the town. 1hevillagers tried to cUI down the trees on the sliding part tomake it lighter and perhaps to slow it down. But the effortcame too late. One September morning, the" holemountain crashed dO\I n. Millions of tons of rock and >I,iIsmashed over the town at 100 miles an hour. dc-trnying thetown and killing many people.

Not all landslides arc <i"i big or as harmful. Some occurwhere there arc no people: some move only a few tons ofsoil. Big or small. landslide ••are brought down by oneforce. Can you think what force that is'? What force causesall things on earth to come down?

189

5. Why does water almost always run downward tothe lowest point? (Answers will vary. Water flowsdownward because of the pull of gravity.) Whatwill the water carry with it as it flows downward?(soil)

6. What do raindrops do to the soil? (dislodge parti-cles and move them about)

7. Do you think splash erosion causes more damageto a sloped field or a flat field? Why? (a slopedfield, because the splashes will flow downward,eventually creating sheet erosion)

8. Have you ever seen a stream or river after a heavyrain? How did it look? (swift, muddy) What do youthink made it look muddy? (eroded soil in thewater)

Display the song "My Country, 'Tisof Thee" from page 33 of the HomeTeacher Packet and sing it with yourchild before asking question 9.

9. What does rills mean in this line, "I love thy rocksand rills, / Thy woods and templed hills?" (smallstreams)

Conclude the discussion. Display the gully on page 32of the Home Teacher Packet. Ask your student whatmuch-loved national landmark is similar to the gully,

SCIENCE 4 HTE

ErosionThe carrying of soil from one place to another i, called

erosion. Water and wind cause most erosion. Wind blowssoil about in many directions. But water almost alw ays runsdownward to the lowest point. Why is that') What can youguess about most erosion caused by running water?

Water ErosionRunning water carries away soil in many ways. When

raindrops strike the ground, they loosen and push bits ofsoil. This quiet work of the rain is splash erosion. Heavieror longer rains often run off slopes in sheets, carrying awayloose soil and even small stones. What do you think thiserosion is called? It ib sheet erosion.

When running water washes away soil, it creates newlandforms. Sometimes a downpour gougc..:sa ditch, a gully.in the surface of the earth. If the gully continues to carryrunning water, it is a rill. a small stream. What doc> thisline from "My Country. 'Tis of Thee" mean: "I love thyrock> and rills. Thy woods and templed hills"?

Streams, especially flooded streams, erode the surface ofthe earth. Rivers carve valleys and gorges and widen outtheir banks. How fast a valley or gorge gets worn into thecrust depends on many thing': how hard or soft the rock is.how much water there is, how fast the water is moving, andhow .Iong the water has been moving.

190

but much larger. (the Grand Canyon) Ask him why hethinks the Flood could have created a huge canyon inthat location but not in other places throughout the earth,(the type of soil and the swift downward flowing of theriver) Emphasize the creationist belief that the GrandCanyon is a result of the Flood and not of millions ofyears of slow erosion. Tell your student that since theevolutionists do not believe in the Flood, they can onlyassume that the canyon was formed by the same slowprocesses we see today,

Evaluating the LessonDirect an observing activity. Take your student on awalk through the neighborhood, Tell him to look forevidence of erosion, soil creep, or even small landslides,Allow him to make brief notes about problem areas,When you arrive back home, instruct your student towrite a description of two to three of the problems hefound and their locations.

For Your InformationThe Grand Canyon is the world's most spectacular

example of the result of erosion, Yet early explorersconsidered it nothing more than an obstacle standing


Probably the most spectacular gorge in the world is theGrand Canyon. It runs for well over 200 miles and is a miledeep in places. 1 he sunsets bla/e across the walls. turningthe layers of rock orange and red. Evolutionists look at thatvast canyon and at those beautiful layers of rock and saythat the earth is millions of years old, that no young earthcould have such a deep gorge in it.

Creationists look into the canyon and see the power ofGod and find evidence of the great Flood. When the Floodwaters went down, they swept across whole continents withunimaginable force. The material underneath was still softand unsettled. Under such conditions, much erosion couldhappen quickly. A young earth in a mighty flood wouldindeed have such a gorge. When the river no longer carriedthe huge amounts of water and the sediment hardened,erosion slowed down. The layer> in the canyon wallsnarrow at the bottom. showing such a change in rate.

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between them and the water of the river that flowedthrough the canyon, Even as late as 1857, an explorercalled the canyon a "profitless locality," believing thathis party was the first and would be the last to see thehuge gorge, He was wrong on both accounts.

Father Francisco Tomas Garces gave the river thatflows through the canyon the name Colorado becauseof its red color resulting from the soil it carried, He wasone of the first to make the climb down the steep canyonsides in 1776 to visit the Havasupai Indians as a mis-sionary, Today, the Havasupai continue to live in iso-lation at the bottom of the Grand Canyon as they havefor centuries.

The rims of the canyon vary from four to fourteenmiles apart On the average, the depth of the canyon isone mile, A dramatic change in the climate and vege-tation takes place as one gradually ascends to the north-ern rim of the canyon, The floor of the canyon has aclimate and vegetation similar to that of a Mexicandesert, At the top of the northern rim, the climate chang-es to that of southern Canada, In winter, this northernrim is closed to traffic because of snow, but the southernrim remains open to the public year-round,

The Grand Canyon was made a national park in1913, After visiting the canyon in 1903, Theodore Roo-sevelt stated that it should be kept "as the one greatsight which every American should see,"

219

Lesson 50Water Erosion


Preview LessonObjectives Introducing the Lesson ---

Direct a demonstration. Set the jar on a table whereyour student can see it. Remind him that water instreams and rivers moves, sometimes very rapidly andsometimes so slowly that it looks as if it is not movingat all. Using the spoon, gently stir the water in the jar,being careful not to touch the soil. Ask your student totell what water picks up as it moves along. (sand, soil,and rocks) Stir the water faster. Ask him what happenedto the soil and pebbles as the water began to move faster.(More was picked up and carried along by the swift-moving water.) Continue to stir the water faster untilalmost all the soil and pebbles are carried in the swirlingwater.

Remove the spoon from the water quickly. Ask yourstudent to observe what happens to the water and theload of soil it is carrying. Ask him which particles settlefirst: the pebbles or the soil. Instruct him to give somereasons that streams and rivers slow down and to predictwhat happens in the process.


• Predict the effects of water on a flat field and a slopedfield.

• Describe the effects of slowing water on the soil it iscarrying.


• 1 large jar.• Several small pebbles.• Fine potting soil. *• 1 spoon.• 2 half-gallon milk cartons.• 2 oblong cake pans.• 1 sprinkling can.• 2 quarts of water.• 1 ice cube.

Prepare:• The jar by covering the bottom of it with soil and the

small pebbles and adding enough water to fill it al-most to the top.

• The two milk cartons by filling them with soil towithin one inch of the top. Place one carton into eachoblong cake pan.

• The sprinkling can by filling it with the water.

220 SCIENCE 4 HTE

Water not only picks up material, but it also laysmaterial down in other places. 11 deposits soil as it slowsdown. What arc some things that would cause a river toslow down enough for the soil and other material to settleout of it'?

When a river flows into another body of water, it slowsdown. It pushes out into the other water and fans out. Itthen deposits soil in a shape something like a fan. We calltbat triangle a delta. Delra is the fourth letter in the Greekalphabet. What do you think that letter looks like'!

When a river floods. the water that goes over the banksslows down when it hits the land. The sediment in the watersettles out, laying down a flood plain.

192

Teaching the LessonDirect a text activity on pages 192-96. Use the follow-ing statement and questions to initiate your student'sinterest in what he is going to read.1. Find out if the predictions you made at the end of

the activity were correct.2. What is a stack?3. What is a glacier?

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Why do you think a river slows down as it enters

a lake or ocean? (The water in the lake or oceanis moving but not as swiftly as the river is flowing.)

2. What is a delta? (soil deposited in the shape of afan or a triangle)

3. What do we call sediment that remains after floodwaters have receded? (flood plain)

4. Name three things that ocean waves can form.(wave-cut cliffs, sea caves, and stacks)


Ocean water is it powerful force for eroding the surfaceof the earth. The steady rushing of the waves can formcliffs, caves, and stacks.

A wave-ell! cliO-is a steep, slanted "all of earth thatborders the sea. The cliffs at the Strait 01 Dover in southernEngland contain chalk. They arc commonly called theWhite Cliffs of Dover. Do }OU think chalk would be casilveroded?

Sometimes the wave, wear a hole in a cliff. This hole isa sea carc. Perhaps you have read a story about someonewho hides treasure in such a place. Would that he a goodplace to hide treasure?

When ocean water erodes softer rock from around hardrock, a stack appears. S13c", arc columns or rowers of rockstanding out of the sea. lhe sand and bib of rock and shellcarried in seawater work like Iilcs on rock, wearing it awayin the push and pull of \\ aves.

193

You may wish to explain to your childthat most waves are caused by windspushing against the surface of theoceans. They begin as ripples and con-tinue to grow as they approach theshore. All waves have the ability tocause erosion, but the bigger a waveis, the more power it has to carry soiland sand away. A hurricane or a tsu-nami [tsoo-na'me] (tidal wave) canerode a great deal of the land in a shortamount of time.

221

If oceans only wore down the shores, the continentsmight dwindle to islands after a while. God has providedfor the rebuilding as well as the eroding of the earth's crust.Ocean waves wear down shores; ocean currents build themup and make other landforms in the sea.

A spit is a bar of sand that reaches out from an island orthe shoreline. It is deposited there by the working of theocean. A hook is a spit with a bend in it.

Barrier islands are sandy beaches that are notconnected with the mainland. Why do you think they arecalled barriers" A tombo!o is a beach of sand or gravel that-connects two islands or an island and the mainland.

194

5. Look at the picture on page 194. Name the fourlandforms that God has provided for the rebuildingof the earth's crust. (spit, hook, barrier island,tombolo)

6. What is a glacier? (a huge mass of ice movingslowly)

7. Why do you think that glaciers do not form every-where it snows? (The snow and ice melt each year,and the piles made in one year are not thick enoughto form the huge blocks of ice.)

8. Where might you find the landforms created byglaciers? (near the North or South pole)

9. Look at the picture of the fjord on page 195. Whydo you think that there are many fjords in Norway?(Answers will vary, Much of Norway is borderedby the Norwegian Sea, This very mountainouscountry is close to the Arctic Circle-so close, infact, that the northernmost part of the country lieswithin the circle.)

222

Frozen water also makes changes on the earth. What isone way that freezing water weal her S the surface? A glacieris a huge mass of ice moving slowly. When snow falls onsnow, and more snow falls on that, the weight forms a greatblock of ice. When that block gets heavy enough, it beginsto move. scraping over the surface of the earth andsometimes shoving rocks and soil ahead of it. Why do youthink that glaciers do not form everywhere it snows'?

The new landforms gouged out by glaciers have namesthat sound like something out of science fiction, A cirque(pronounced surk ) is a large round hollow scooped out bya glacier. When ice melts and water fills a cirque, amountain lake called a lam forms. AjJord (pronounced[yord; is an inlet from the sea that has been made deeperby a glacier. fjord is a Norwegian word. Why do you thinkNorway has many fjords'

195

SCIENCE 4 HTE

Glaciers, like ocean water and streams, deposit materialtoo. The rock and soil pushed along by the snout or frontedge of the glacier are called till. Ridges of till are left whenglaciers melt back. Moraines and drumlins are two kinds ofhills made by glaciers,

Glaciers can deposit material when they melt as well.Meltwater carries earth and rock much as a stream does.Also, when glaciers melt they send billions of gallons ofwater flowing to streams far below them. Meltwater is freshwater, which is water that is good [0 drink. God designedthe glaciers to store water in the coldest months when wateris not usually scarce and to release it in wanner monthswhen streams and reservoirs are low,

196

Conclude the discussion. Ask your student to name thetwo types of hills that glaciers form, (moraines anddrumlins) Tell him that scientists consider these hillsimportant because they show how far glaciers havecome in the past. Rock flour is the name scientists havegiven the finely ground pieces of rock and earth that arecarried away by glaciers, This rock flour gives the wa-terfalls and streams that flow from glaciers their beau-tiful colors.


About Water ErosionI. Get two half-gallon milk cartons, two oblong cake

pans, some fine potting soil. a spoon. a sprinkling canof water, and an ice cube,

2. Cut one side out of each carton. Fill both with soilwithin one inch of the top. Make a "riverbed" in eachcarton with the handle of the spoon. Put the cartons inthe baking pans. Lift one end of one carton about fourinches, keeping the spout at the top.

3. Sprinkle one quart of water slowly into the top of thetilted carton. Watch what happens to the soil. Sprinklethe same amount of water into the other pan that issitting level. What happen> to that soil'!

4. Now tilt the second carton and put the ice cube at thetop. Let the ice cube move and melt a. it will. Recordall your observations.

197

Evaluating the LessonDirect a Finding Out activity on textbook page 197and notebook page 58. Place the pans on the floor ora low table. Allow your student to make a "riverbed"in each milk carton of soil. Elevate one end of one milkcarton about four inches. Instruct your student to predictwhat will happen when water is poured into the tiltedcarton and to write his predictions in the correct placeon the notebook page. Allow your student to carefullypour one quart of water from the sprinkling can into thetop of the tilted carton. Tell him to record his observa-tions; then have him predict what will happen whenwater is poured into the flat carton. Pour one quart ofwater into the flat carton.

Tilt the flat carton and place the ice cube at the topof the' 'riverbed." Direct your student to watch the icecube and to record his observations.

223

neme _

Predictions Resuhsto the soil to the wlter

tilted

flat

Can you think of a way to keep the soil from being carried away by the water? _

The ice _

Thesoil _

01990 Bob Jones Ullive.sily P,ess. Reproductlonprol\iblted

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For Your InformationScientists have estimated that approximately 10 per

cent (6,020,000 square miles) of the earth's land surfaceis covered by glaciers. Ninety per cent of this ice canbe found in Antarctica, covering the continent so thicklythat just over 2 per cent of the land can be seen. Hugeglaciers, such as this one in Antarctica, are called icesheets.

Radio echo soundings have enabled scientists tomeasure the depth of the Antarctic ice sheets at almost3 miles. They have also discovered several lakes underthis ice, the largest of which covers over 3,000 squaremiles.

On a temperate glacier, such as the ones found inparts of Canada, Scandinavia, and New Zealand, theyearly snowfall may be as much as 16 to 30 feet. Thissnow may be converted to glacial ice in as little as 5years. But on the much colder glaciers of Greenland andAntarctica, it may take the same amount of snow asmuch as 3,000 years to convert to ice because of thesmaller amounts of yearly snowfall and the inability ofthe ice to thaw and refreeze quickly.

A thin film of water between the ice and the rock itcovers enables the glacier to move. It slides easily oversmooth rock, pushing against any bumps in the rockwith such pressure that the glacier may bend and crack.If the ice on the underside of the glacier has reachedthe melting point, some of the ice forced against anobstacle will melt, flow around the obstacle, and oftenrefreeze on the other side where the pressure is not sogreat.

Some glaciers have been known to "surge" or ad-vance quickly for short periods, sometimes as much asseveral yards per hour. The Quarayaq Glacier in Green-land was recorded to flow at the rate of 65 to 80 feetper day in 1982. Such forward movement can actuallybe seen, heard, and felt as the ground shakes violently.

SCIENCE 4 HTE

Lesson 51PreventingErosion


PreviewObjectives


• Identify soil-conserving plowing methods.• Distinguish between soil-conserving practices and

erosive practices.


• 2 half-gallon paper milk cartons used in Lesson 50.• 2 oblong cake pans.• Clean, fine soil (about 1 gallon).• 1 spoon.• 1 sprinkling can.• 2 quarts of water.• 2 large measuring beakers. *t

Prepare:• The milk cartons by filling them with soil to within

one inch of the top.


Direct a Finding Out activity on page 198. Instructyour student to follow the directions for Steps 1 and 2on page 198. Allow him to plow the soil in each panaccording to Step 3 and to place the measured beakersunder the spout of each carton to catch the runoff. Askhim which carton will lose more soil when water ispoured onto it. (Answers will vary.) Allow him to pourwater on each carton, using the sprinkling can. Discussthe results with your student. Explain to him that thehorizontal plowing is called contour plowing, plowing"with the land." Direct him to record his observationson notebook page 59.

Chapt, 12: Lesson 51

About Controlling Erosion

I. Get the same equipment you used for the Finding OutAboUI Water Erosion, except you will not need an icecube. You will also need two large measuring beakers.

2. Fill both cartons within one inch or the laps with df)soil. Put both in the baking pans and tilt hath cartons.

3. "Plow" vertically in one carton and horizontally in theother, using the handle of the spoon or your fingers.

4. Then slowly sprinkle one quart of water into thevertically "plowed" soil. Watch what happens to thesoil. Then sprinkle another quart of water at the samerate into the other carton. Walch what happens. Collectthe run-off from both cartons vcparatcly. Which kindof plowing prevented more erosion'? Record yourobservations.

198

name _

Plowing method Amount of run-off

Which plowing method would you use? contourWhy? ~A •••n~sw~e"'rs~w!!'i~lI_.!'va~rl:.y. _

~1990 Bob JOnf!~Unive"ity Press ReprodUCtion ptohib,!ed

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225

Wind ErosionWhen wind carries away loose material and hollows out

a basin in the ground, it creates a b!OWOIJI. What docs thename tell about the landform?

Wind deposits sand, building up hills called dunes. Howis the work of the wind on the earth like the work of water?How is it different?

Erosion comes from two Latin word parts that mean"to gnaw off." Why is that a good name for this process?A.II the wearing down of the earth is called degeneration.Hebrews I: II says the earth "shall wax old as doth a gar-ment." The earth will eventually grow old and wear out likeclothes do.

But degeneration is not the only process at work. Godhas also established conservation. ways for energy, soil, andother things to be preserved or renewed. Hebrews 1:3 tellsus that God is "upholding all things by the word of hispower,"

199

You may want to further develop theconcepts taught in the Finding Out ac-tivity to include stripcropping and ter-racing. To demonstrate stripcropping,place a strip of sod perpendicular tothe milk-carton slope and sprinkle the"field," using the sprinkler can. Todemonstrate terracing, build steps inthe soil down the slope, and sprinkleas directed in the activity. Collect andcompare the run-off.

Teaching the LessonDirect a text activity on pages 199-201. Use the fol-lowing question and statement to initiate your student'sinterest in what he is going to read.

1. What is degeneration?2. Find out some ways erosion can be prevented.

Continue with discussion questions. After your stu-dent completes his silent reading, use the followingquestions and statements as a guide to discuss the pageshe read.1. Look at the picture on page 199. What conditions

do you think are present when most wind erosion

226

Some erosion can be jJl\;\t:lltctl with careful use of theland. Farmers keep soil from washing away by contourplowing, plowing "with the land," following the curves of

the hills. Strip-cropping. in which crops arc planted inbands along the contours. also slows down fun-off. Rowsof trees between fields also help stop wind erosion.especially during plowing.

Erosion can also be prevented with responsible methodsof clearing land. Where vast areas arc stripped and burned,as in the great rain forests of South America. nothing cankeep millions of tons of soil from being swept away.Careful planning and cutting rather than totaldestruction can conserve soil and preserve the forests.

Shores. too. can be protected or rebuilt. Seuwatls arcbarriers of steel. wood. or concrete built along the beach.Galveston. Texas. has had a seawall since 1900. when ahurricane whipped the ocean waves across the city withgreat destruction. The Army Corps of Engineers rebuiltpart of the beach in Miami. Florida, by pumping up tonsand tons of sand from under the sea.

A rich topsoil is a finer treasure than the giant sequoiasthat grow from it or the diamonds buried beneath it. It isthe very base upon which our physical life rests. It supportsthe plants that provide our food and replenish our air. Godhas not only provided our earth with good soil. He has alsoestablished the processes by which it is renewed. If we arccareless with the soil, if we do not perceive the great cyclesand endeavor to operate within them, we waste one ofGod's best blessings to Us. We arc to be good stewards ofthis gift: we must use the soil wisely so that the earth maycontinue to bring forth it. bounty.

200

occurs? (Answers will vary. The land is dry. Thereis little plant cover. The winds are high.}

2. What is degeneration? (the wearing down of theearth) Name other things that degenerate, or wearout. (cars, houses, toys, our bodies)

3. What does the word erosion mean? (to gnaw off)Why do you think this is a good name for theprocesses of degeneration of the earth? (Wind andwater seem to "gnaw off' the topsoil.)

4. What things can you do to keep your body fromwearing out, or to conserve it? (Some examplesmight be to eat nutritious foods, to exercise, or toget plenty of sleep.) Although God protects Hischildren, He wants them to take good care of thehealth He has given them. In the same way, Godwants us to take good care of the things He hasgiven us in the earth even though He has providedways for soil and other things to be renewed andpreserved. List some ways that God has providedfor the soil to be renewed and preserved. (Someexamples might be weathering, decaying organicmaterial, or grass and other ground covers.)(BATs: 2c Faithfulness-Responsibility; 3d Bodyas a temple; Bible Promise: I. God as Master)

5. Does erosion affect only farmers? (no)6. Name some ways erosion might be prevented in

your neighborhood. (Possible answers: Housescan be built on terraces. Builders can carefully

SCIENCE 4 HTE

"Heaven find earth shall p(JS,~Glnly. but my wnrds shall notpas» (Jlt'aL ... Luke 21:33

201

clear only the land needed for a project, cover thesoil with straw to keep it in place during construc-tion, and plant trees and grass when the job hasbeen finished. The sides of gullies can be plantedwith a ground cover or lined with concrete.)

Conclude the discussion. Most of the obvious erosionproblems are a result of man's improper use of the soil.Discuss the ways that soil erosion can affect your stu-dent. Tell him that the estimated yearly cost of erosionin the United States alone reaches into the billions ofdollars.

Ask your student to read Luke 21:33. Discuss withhim the seemingly permanent cycle of weathering anderosion that brings about constant change in the earth.Ask him whether, according to this verse, these thingsreally are permanent. One day, all the things that we arefamiliar with will pass away-the earth, moon, stars, andsun. God will create a new heaven and earth, and Jesuswill be the light. But God's Word has never changed,and it never will. It will not pass away . (BATs: 8a Faithin God's promises; 8b Faith in the power of the Wordof God)


name _

Across Down

I. __ are a kind of hill made by

glaciers.

5. __ can happen when sedimentclogs rivers and streams.

6. A fan-shaped sediment deposit at themouth of a river is a __ .

7. __ is fresh water flowing from aglacier.

10. "I love thy rocks and __ ."13. Heavy, long rains can cause __

erosion.14. Slow mass-wasting is called __ .16. A __ connects two islands.17. A __ is an inlet from the sea.18. Rock and soil pushed by a glacier is

called __ .19. A __ is formed by the weight of

snow on top of snow forming ice.20. Water expands as it turns to __ .21. The __ is the world's most

beautiful gorge.

I. The wearing down of the earth isknown as __ .

2. A __ is a form of swift mass-wasting.

3. A __ is a bar of sand deposited bythe ocean's work.

4. __ the Great ruled southernEngland over one thousand years ago.

8. Rich surface soil is called __ .9. __ breaks rocks into soil.11. Dead plant and animal material is

called __ .12. Farmers __ plow with the slope of

a field.15. __ means "to gnaw off."

01\190 Bob Jon,. Unlver.lty Pre ••. R'productlon prohibited.

0-Sdence4Notebook Packettesecn stEvaluatfng the Lanon

Evaluating the LessonDirect a notebook activity on pages 60~61. Ask yourstudent to read the directions; then tell him to completethe puzzle.

For Your InformationLand has historically been considered a limitless

resource in the United States. During the 1500s and1600s, the New World was looked upon as a land ofplenty, largely due to the reports of fertile soil and hugeamounts of timber and fur pelts. This feeling of limitlessplenty continued through the early periods of expansionand settlement. Government officials perpetuated theidea that it was the young nation's duty to reap thebenefits of the land to the west. The Homestead Act andinventions such as barbed wire and the steel plow urgedsettlers ever westward.

Settlers cleared small patches of forest for farms,moving on when the land became barren from overuse.The openness of the Great Plains gave the settlers afeeling of inexhaustible plenty. The prairie soils wereable to support large fields and great herds of grazingcattle. But little attention was given to soil conservation

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61

name _

Complete the puzzle with word. from the chapter. Clue. tor the puzzle are on PIII8 81.

C1990 Bob Jones Universily Press, Aeproduclionprohibited.

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lesson 51

Ev.luatlflg the lElSlOfl .60

throughout this period of growth, resulting in a greatloss of soil to erosion.

In the early 1930s a long drought turned much ofthe farming areas of the Great Plains into the Dust Bowl.Parts of Texas, Oklahoma, New Mexico, Colorado, andKansas were the hardest hit, with drought and prairiewinds working together to blow away billions of tonsof precious topsoil. Once-productive farmland was leftuseless. To make matters worse, the nation was in thethroes of the Great Depression. Jobs and money werescarce. Many fanners lost their land because it couldnot produce enough crops for them to pay their bills.As a result of this great loss, the United States Congresscreated the Soil Conservation Service in 1935 to educatefarmers, builders, and home owners in proper conser-vation practices.

SCIENCE 4 HTE

SupplementConcepts

Concepts are short statements of scientific knowl-edge. Although your student will learn about each con-cept as each lesson is taught, it is not necessary for himto memorize the concept.

Chapter 1Lesson 1

• What a person believes about the beginning ofthings is determined by faith.

• God's description of how things began is calledthe Creation Model.

• The Evolution Model describes ways in whichsome scientists think that the universe might havebegun by itself.

• The Break-Away Theory says that the moon pulledaway from the earth leaving a hole that became thePacific Ocean.

Lesson 2• The Capture Theory states that at one time themoon orbited the sun. When the moon came closeto the earth in its orbit, the earth captured the moon,which then orbited the earth instead.

• The Condensation Theory states that the earth andthe moon were both formed when a mass of dustand gas condensed.

• God's Word says that God spoke and made themoon out of nothing.

Lesson 3• Evolutionists believe that the moon is millions ofyears old.

• Changes and activity on the moon (transient lunarphenomena) help to prove that the moon is youngand active.

• The thin layer of dust found in the low areas onthe moon helps to prove that the moon is young.

• The moon is gradually getting farther away fromthe earth. Its present distance helps to prove thatthe moon is not as old as evolutionists say it is.

Lesson 4• The moon reflects the sun's light.• The apparent movement of the moon across the

sky is caused by the earth's rotation.• In the ancient Near East, people began each monthat the appearance of a new moon.

• God will use signs such as the darkening of thesun and moon to signal the end of this age.

Concepts

Chapter 2Lesson 5

• Adult insects have three pair of legs, three bodysegments (head, thorax, and abdomen), and usuallyone pair of antennae.

• Insects may develop by incomplete metamorphosis(egg, nymph, and adult) or by complete metamor-phosis (egg, larva, pupa, and adult).

• The insect order that includes the grasshopper,cricket, praying mantis, and cockroach is calledOrthoptera. These insects have two pair of wings,one outer pair like heavy paper and the other cov-ered pair like crisp, clear silk.

Lesson 6• The dragonfly group (Order Odonata) has two pairof membranous wings and thin bodies.

• The nymph stage of the dragonfly group lives inthe water.

• The aphid group (Order Homoptera) has two pairof wings or is wingless. Members of this group usetheir mouth parts to pierce the outer covering of aplant and to suck plant juices.

• The bug group (Order Hemiptera) has piercing,sucking mouth parts and two pair of wings. Thefront pair of wings is thicker where the wings jointhe body and thinner toward the end.

Lesson 7• Butterflies and moths (Order Lepidoptera) can bedistinguished from one another based on the fol-lowing characteristics: body type, antennae, posi-tion of wings, time of activity, and pupal stages.

• Members of the beetle group (Order Coleoptera)have two pair of wings. The front wings are hardand usually shiny and often form a shell-like cov-ering for the thin hind wings underneath.

• Members of the fly and mosquito group (OrderDiptera) have one pair of wings that are thin, al-most transparent, and veined. Most have suckingmouth parts.

Lesson 8• Bees have two pair of wings. The front pair islarger than the back.

• With the exception of queen ants and males, mostants do not have wings.

• Both bees and ants live in large groups called col-onies. They belong to the Order Hymenoptera.

• Bees use special dances to inform other membersof the hive of new food sources.

• Many ants use special odor trails to lead membersof the colony to food.

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Lesson 9• Fleas do not have wings.• Fleas have sucking tubes designed for eating andlegs designed for leaping.

• Insects can be separated into groups based on thenumber and structure of their wings.

Lesson 10• Arachnids have four pair of legs, two body divi-sions (head and thorax form one body division),no antennae, and no wings.

• Myriapods have many legs. The group includes thecentipedes and the millipedes.

Chapter 3Lesson 11

• Atoms are made up of three main parts: protons,neutrons, and electrons.

• Electricity is caused by an imbalance of electronsin atoms.

Lesson 12• St. Elmo's fire is a result of static electricity.• Objects that have the same electrical charge repeleach other. / /

Lesson 13• Out-of-balance electrons tend to get back intobalance.

• Electricity needs a complete circuit in order towork.

Lesson 14• Electricity and magnetism are closely related.• Electricity can be generated with magnets.

Chapter rLesson 15

• Fungi do not make their own food.• Mushrooms, molds, and mildews are all fungi.• Fungi reproduce by spores.

Lesson 16• Algae, mosses, and liverworts are tubeless plants.• Algae, mosses, and liverworts carryon photo-synthesis.

Lesson 17• Ferns are tubed plants.• Ferns do not have seeds.• Ferns reproduce by spores.

Lesson 18• Conifers produce seeds in cones.• Conifer leaves have two basic shapes.• Most conifer leaves are evergreen.

Lesson 19• Flowering plants are divided into monocotyledonsand dicotyledons.

• Flowering plants produce seeds in flowers andfruits.

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Chapter 5Lesson 20

• Length is the distance of an object measured fromone end to the other.

• Measurements must be expressed in numbers.Lesson 21

• The most widely used system of measurement inthe world is the metric system.

• The metric system is based upon units of ten, mak-ing multiplication and division easier.

Lesson 22• Area is measured by multiplying length timeswidth.

• Area is expressed in square units.Lesson 23

• Volume is expressed in cubic units.• An object immersed in water will displace a vol-ume of water equal to its own volume.

Chapter 6Lesson 24

• God has designed the digestive system to changefood into a form that the body can use.

• Digestion begins in the mouth where the salivasoftens and moistens the food and changes somestarches into sugar.

• The tongue moves food and detects four differenttastes.

• The teeth break food into small pieces.Lesson 25

• The throat, or pharynx, branches into two "pipes"below the back of the mouth.

• The trachea is the windpipe.• The esophagus is the food pipe.• Food passes through the esophagus to the stomach.

Lesson 26• Food is mixed with digestive juices in the stomach.• Food is mixed by the movement of the walls of thestomach.

Lesson 27• The small intestine is a coiled tube about 23 feetlong.

• The small intestine is the main digestive organ.• Digestive juices formed in the small intestine, thepancreas, and the liver are added to the food.

• The large intestine absorbs water and salts.

Chapter 7Lesson 28

• The moon has mountains, plains, craters, and rills.• The mountains on the moon are jagged becausethere is no erosion or weathering.

SCIENCE 4 HTE

Lesson 29• The moon's gravity is one-sixth of the earth's.• At perigee, the moon is closest to the earth; atapogee, the moon is farthest from the earth.

• The moon's temperatures vary greatly because ofthe lack of atmosphere on the moon.

Lesson 30• The moon makes one rotation as it makes onerevolution.

• Inertia and gravity are the two forces that keep themoon in its orbit around the earth.

Lesson 31• The moon reflects the light of the sun. From theearth we see different phases of the moon.

• The word gibbous means' 'humpbacked."• The word waxing means' 'to show a progressivelylarger light surface."

Chapter 8Lesson 32

• God has given every animal the equipment andbehaviors it needs to protect itself.

• Some animals look like other more dangerousanimals.

• Some animals look like their surroundings.

• Some animals are brightly colored to warn orfrighten other animals.

Lesson 33• Some animals have appendages that help them toprotect themselves.

• Some animals have coverings that protect themfrom harm.

• Some animals have the ability to release chemicalsor electricity when they are in danger.

Lesson 34• Most animals use some type of behavior, or tactic,to defend themselves.

Chapter 9Lesson 35

• Light is waves of radiant energy from the sun andother sources.

• All light waves travel at the same speed in emptyspace.

• Light travels in a straight line until somethingblocks it.

Lesson 36• The eye is a remarkable instrument.• Each part of the eye performs a special function.• If some of the functions of the eye are imperfect,glasses or contact lenses can provide correction.

Concepts

Lesson 37• Light reveals color.• The color of an object depends upon what kindsof light are reflected from it.

• Colors may be combined to form other colors.• Colors of objects vary in intensity depending uponhow the objects reflect or absorb light.

Lesson 38• Reflection is the return of light from a surface.• Reflectors are surfaces that return light.• Mirrors are polished reflectors that return an image.

Lesson 39• The laser is a device that amplifies light.• The laser has many uses.

Chapter 10Lesson 40

• Work gets done when a force makes somethingmove.

• Force times distance equals work.• Simple machines make work easier.• An inclined plane is a slanting surface that con-nects one level to a higher level.

• An inclined plane multiplies a small force into alarger one.

• An inclined plane is a simple machine.Lesson 41

• A fixed pulley changes the direction of a force.• A movable pulley multiplies a force.• A wheel and axle changes the direction of a forceand can multiply the force.

Lesson 42• A lever is a bar that turns on a point, or a fulcrum.• The closer the load is to the fulcrum, the easier itis to move the load.

• A lever multiplies force.Lesson 43

• A wedge is two inclined planes put together.• A screw is a spiraled inclined plane.

Chapter 11Lesson 44

• Leaves vary in size and shape and can be groupedaccordingly.

Lesson 45• Leaves vary in size and shape and can be groupedaccordingly.

Lesson 46• Trees can be identified with a classification key.

Lesson 47• A tree is a living thing that has basic needs.

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Chapter 12Lesson 48

• Rocks can be broken into smaller pieces by wind,frost, heat, water, or roots in a process called me-chanical weathering.

• Rocks can be broken down when gases mix withwater in a process called chemical weathering.

• The rich soil at the surface that is mixed withorganic matter is called topsoil.

Lesson 49• Mass-wasting occurs when large amounts of earth

or rock slide downhill.• The moving of soil is called erosion.• Creationists see the Grand Canyon as evidence of

God's power and of the great Flood.

Lesson 50• Water deposits soil in new places as it slows down.• Water slows down as it enters another larger body

of water or as flood waters move over land.• Ocean waves erode land, forming cliffs, caves, and

stacks.• Ocean currents build up the land and make new

landforms.• Glaciers move and deposit soil in new places in

much the same way that water does.

Lesson 51• Wind is a cause of erosion.• Degeneration is the wearing down of the earth.• Conservation is the preservation or renewal of nat-

ural resources such as topsoil, forests, and water-ways.

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Materials List

Chapter 1Family Time 1

• 3 cans refrigerated biscuit dough. *• + cup melted margarine.

• f cup granulated sugar.• 2 teaspoons cinnamon.

Lesson 1• 1 napkin.• 1 dampened towel (optional).• 1 loaf of "Break-Away Bread" (prepared in Fam-

ily Time 1).• 1wrapper from a can of refrigerated biscuits.

Lesson 2• 1 soccer ball or basketball.• 1 container of baby powder.• SCIENCE 4 Home Teacher Packet, pp. 1-4.*t

Lesson 3• 1 container of baby powder.• 3 sheets of red (or blue) construction paper.• A Write It flip chart. *t

Lesson 4• Plastic tack.• 1 globe.*t• 1 softball.• SCIENCE 4 Notebook Packet. *t• A three-ring binder. *

Chapter 2Lesson 5

• Home Teacher Packet, pp. 5-6.• 1 plastic comb.• 1 metal nail file.• A Write It flip chart.• Several field guides or resource books about

insects. *

Lesson 6• 2 feet of yam.• Small piece of scrap paper.• 1 stapler.• 1 four-holed bubble pipe. *• Bubble solution.

Family Time 7• 1 plastic margarine container.• 5 resealable sandwich bags.• 2 Popsicle sticks or flat toothpicks.• 2 small weighted objects (large spool of thread or

a small box of matches).Lesson 7

• 1 flashlight.

SCIENCE 4 HTE

Family Time 8

• 1 large wide-mouthed jar.• 1 sealed can or cardboard tube (about 1" smaller

in diameter than the jar).• Slightly damp soil and sand.• Small sponge.• Swatch of loosely woven cloth.• Black construction paper.• Cellophane tape.• 1 large rubber band.• Ants for the ant farm. *t

Lesson 8• 1 handkerchief or square of cloth for a blindfold.• 20 squares (2" x 2") of tissue paper.• 1 resealable plastic bag.• Perfume or vanilla extract.• Several cookies or other treat.• Bread crumbs or jelly.• Tiny pieces of banana and apple. *• Bits of walnuts. *• Ant farm prepared in Family Time 8.• Ants (different type from the ants in the ant farm)

for experiment on Day 4. *Lesson 9

• 5 insects in resealable plastic bags.• Small magnifying glass (optional).*t• 5 insect pins (optional)." (NOTE: Number 3 insect

pins work well for average-sized insects. Insectpins are recommended because of their slendernessand extra length, but straight pins may besubstituted. )

• 1 toothpick.• Small section of cardboard (about 3" x 3 ")

(optional).• Viewing jars and boxes (optional).• A Write It flip chart.

Lesson 10• Home Teacher Packet, p. 7.• Spider's web.*• I ball of yam.

Chapter 3Lesson 11

• Home Teacher Packet, p. 8.• 1 balloon.• 20 inches of string.• I wool sweater, scarf, or pair of gloves.

Lesson 12• 2 balloons.• String.• 1 wool sweater or pair of gloves.

Family Time 13• An old orange, cantaloupe, or lemon. *• A large glass jar.

Concepts

Lesson 13• Compass. *t• 1 dry-cell battery (1.5 volt). *• 7 feet of #20, #22, or #24 insulated copper wire. *t• I pair of wire cutters. *• 1 knife switch. *t• I glass or ceramic insulator from a telephone or

electrical wire (optional). *

Lesson 14• Home Teacher Packet, p. 9.• 16+ feet of #20, #22, or #24 insulated copper

wire.*t• 1 iron bolt or rod between 4" and 6" long. *• Several paper clips.• 1 knife switch. *t• 1 pair of wire cutters. *• 1 dry-cell battery (1.5 volt). *t• The galvanometer from Lesson 13.• 1 felt-tip pen (optional).• 1 bar magnet. *t• 1 toilet tissue tube.• 1 piece of cardboard.• Iron filings. *t

Chapter 4Lesson 15

• Moldy orange, cantaloupe, or lemon from FamilyTime 13.

• 1 magnifying glass.*t• 1 large straight pin (optional).• Samples of blue cheese and Camembert cheese

(optional). *• Home Teacher Packet, p. 10.

Lesson 16• Home Teacher Packet, p. 11.• Pond water or water from a fish tank with visible

algae.*• 1 microscope. *t• 1 microscope slide. *t• 1 microscope cover slip. *t• 1 medicine dropper.*t• 1 toothpick.

Lesson 17• Home Teacher Packet, p. 12.

Family Time 18• 1 shopping bag.• Home Teacher Packet, p. 13.

Lesson 18• Home Teacher Packet, p. 14.• A Write It flip chart.• Scissors.• 1 magnifying glass. *t• Several spruce needles. *

Lesson 19• Home Teacher Packet, p. 15.• 2 light-colored felt-tip pens (optional).• 2 wildflowers or cut flowers. *• 1 magnifying glass. *t

235

Chapter 5Lesson 20

• A Write Tt flip chart.• 1 foot ruler.• 1 large map of the United States.*t• 1 paper cube.• Home Teacher Packet, p. 16.• 1 brightly colored felt-tip pen.

Family Time 21• 1meter stick. *t• Balance scale with mass set. *t• Masking tape or chalk.• 1 felt-tip pen.• 1 white potato.• 1 metal teaspoon.• 1medicine dropper. *t• 2 medicine bottles marked by milliliters. *• A stopwatch] or watch with a second hand.• 1 object to be weighed.• Home Teacher Packet, p. 17.

Lesson 21• 1 one-foot ruler.• 1 yardstick.• 1 pint container.• 1 quart container.• 1 gallon container.• 1 thirty-centimeter ruler.• 1 meter stick. *t• 1 liter container.• 1metric weight, from mass set. *t• One piece of string, 1meter long.

Lesson 22• A Write It flip chart.• 4 paper squares (10 em x 10 em).• 1 metric ruler.• 1 sharpened pencil.• 1 sheet of centimeter graph paper. *• Several flat objects to measure.

Lesson 23• A Write It flip chart.• Prepared cube from Lesson 20.• Graduated cylinder. *t• A small amount of water (about 1 cup).• 1 small stone.• 1 blue crayon.• 1 yellow crayon.

Chapter 6Lesson 24

• A Write It flip chart.• Ilemon.*• 1 knife.• 1 drinking glass.• 1 cracker.• 1 orange segment or apple slice. *• Home Teacher Packet, p. 18.

Lesson 25• 1 bowl (soup or cereal).• 1 piece of red construction paper.• 1 cardboard tube from paper towels or wrapping

paper.• 2 small balloons.• 1 vacuum-cleaner hose. *• Transparent tape.• 1 quart bottle filled with water.• 1 label.• 1 felt-tip pen.• 2 flexible drinking straws.• Home Teacher Packet, pp. 18~19.

Lesson 26• The model of the digestive system as far as you

constructed it in Lesson 25.• Home Teacher Packet, p. 18.• 1 blender (or a dishpan).• 1 quart bottle filled with water.• 1 label.• 1 felt-tip pen.• 2 flexible straws.• 2 or 3 cups of finely chopped vegetables and/or

fruits. *Lesson 27

• The model of the digestive system used in Lesson26.

• 1 small dishpan.• 1 fluffy hand towel.• 1 pail.• 1 sponge.• 2 quart bottles.• 2 labels.• 1 felt-tip pen.• 6 flexible straws.• 1 paper towel.• 1 tablespoon of table salt.• 1 tablespoon of sugar.• 1 package of unsweetened Kool-Aid. *• 1 tablespoon of lemon juice.• Home Teacher Packet, pp. 20-21.

236 SCIENCE 4 HTE


• 2 cups flour.• 1 cup salt.• 2 cups water.• 4 teaspoons cream of tartar.• 2 tablespoons cooking oil.• Food coloring (optional).

Lesson 28• 1 apple.*• 1 pie pan.• Play dough or modeling clay, prepared in FamilyTime 28.

• Home Teacher Packet, p. 22.Family Time 29

• A large salad or mixing bowl with completelyrounded bottom, at least 15 inches in diameter.

• Chicken wire (2' x 2').*• 1 flat pan for mixing.• 2 pounds of plaster of Paris. *• 2 pounds of lime. *• Strips of cloth to cover completely the surface ofthe bowl.

• 6 marbles and small, hard balls of various sizes.*• 1 bicycle air pump or rubber tube. *• Shellac (optional).*

Lesson 29• A Write It flip chart.• 1 globe, 12 to 16 inches in diameter. *t• 1 rubber ball, about one-quarter the size of theglobe.

• Ball of string.• Strip of adhesive tape.• 1 bathroom scale.• 1 pear.*• 1 apple.*• Home Teacher Packet, p. 23.

Lesson 30• 1 dictionary.']• 1 strip of wrapping paper (2' x 6").*• 1 book.• 1 rope, 4 feet long.• 1 large stuffed animal.

Family Time 31• 1 dime (optional).• 1 bicycle with a reflector.

Lesson 31• 1 lamp.• 1 orange.• Home Teacher Packet, pp. 24-25.

Materials

Chapter 8Lesson 32

• 1 sheet of red construction paper.• 1 sheet of blue construction paper.• 1 sheet of green construction paper.• 1 hole puncher.• 1 stopwatch+ or watch with a second hand.• Scissors.• 1 plastic margarine container.• 1 felt-tip pen.• Home Teacher Packet, p. 26.

Lesson 33• 1 sheet of drawing paper.• A Write It flip chart.

Family Time 34• Several game markers (beans, buttons, or rocks)for each player.

• 1 card (7T" x 7T"), for each player.Lesson 34


Chapter 9Lesson 35

• 1 short candle.• 1 candleholder.• Matches.• 6 drinking straws.• Plastic tack.• 1 flashlight.• 1 Popsicle stick (tongue depressor or anythingcomparable).

• 1 clear glass of water.Lesson 36

• 1 magnifying glass. *t• Home Teacher Packet, p. 28 (optional).• 1 pencil.

Lesson 37• 1 prism] or clear drinking glass.• Water.• Red, yellow, and blue play dough. (NOTE: SeeFamily Time 28 for play dough recipe.)

Lesson 38• 1 piece of shiny metal (e.g., a metal baking dish).• 1 mirror.• 1 metal spoon (optional).• 1 flashlight.• 1 sheet of black paper.• 1 sheet of white paper.• Home Teacher Packet, p. 29.

Lesson 39• A Write It flip chart.• 1 lamp with shade.• 1 sheet of dark construction paper.

237

Chapter 10Lesson 40

• 4 strips of paper.• Home Teacher Packet, pp. 30-31.• Preweighed packages totaling 20 pounds (e.g., four5-pound bags of potatoes). *

• 1 yardstick or ruler.Lesson 41

• Home Teacher Packet, p. 30.• The paper "planks" used in Lesson 40.• 1 hand mirror.• I flashlight.• 1 large empty thread spool.• 1 wire coat hanger.• Wire cutters. *• String.• 1 small pail or a cup with a handle.• I crank-type pencil sharpener (optional). *

Lesson 42• A Write It flip chart.• 1 lever-type can opener. *• 1 empty, clean can.• Home Teacher Packet, p. 30.• The paper "planks" used in Lessons 40 and 41.• 1 pull spring scale.*t• 1 plastic bag.• 1 set of gram weights or standard mass set.*t• 1 wooden ruler.• String.• 1 chair.

Lesson 43• 1 sheet (8+" x 11") of construction paper.• Scissors.• 1 ruler.• 1 unsharpened pencil.• 1 felt-tip pen.• 1 roll of cellophane tape.• 1 box decorated like a treasure chest and filled with

snacks to be shared at the end of the lesson(optional).*

Lesson 46• Student leaf collection from previous lesson.• 1 conifer branch and cone.*• Several leaf key books (available from libraries).*

Lesson 47• 1 tree.

Chapter 11Lesson 44

• 1 plant press (optional). *• Newspapers or an old telephone book.• Several large, heavy books.• Pictures of poison ivy, poison oak, and poison

sumac.*• 1 paper bag or shoe box.

Lesson 45• Student leaf collection from Lesson 44.• I plant press (optional). *• Newspapers or old telephone book.• Several large, heavy books.• 1 ink pad.*• White or light-colored construction paper.• Several interesting leaves.


• 1 small glass jar.• Water.

Lesson 48• Several small pieces of limestone. *• 1 piece of paper.• 1 cake pan.• Vinegar.• 1 small glass jar prepared in Family Time 48.

Family Time 49• 1 large apple. *• 1 paring knife.

Lesson 49• 15 to 20 small wooden blocks.• 1 small piece of carpet. *• 1 small piece of tile or linoleum. *• I water dropper.• I cup or bowl of water.• Food coloring.• Paper towels.• Home Teacher Packet, pp. 32-33.

Lesson 50• 1 large jar.• Several small pebbles.• Fine potting soil.*• 1 spoon.• 2 half-gallon milk cartons.• 2 oblong cake pans.• 1 sprinkling can.• 2 quarts of water.• 1 ice cube.

Lesson 51• 2 half-gallon paper milk cartons used in Lesson 50.• 2 oblong cake pans.• Clean, fine soil (about 1 gallon).• 1 spoon.• 1 sprinkling can.• 2 quarts of water.• 2 large measuring beakers. *t

238 SCIENCE 4 HTE

Bible Action TruthsThe quality and consistency of a man's decisions

reflect his character. Christian character begins with jus-tification, but it grows throughout the lifelong processof sanctification. God's grace is sufficient for the task,and a major part of God's gracious provision is HisWord. The Bible provides the very "words oflife" thatinstruct us in salvation and Christian living. By obeyingGod's commands and making godly decisions based onHis Word, Christians can strengthen their character.

Too often Christians live by only vague guidance-for instance, that we should "do good" to all men.While doing good is desirable, more specific guidancewill lead to more consistent decisions.

Consistent decisions are made when man acts onBible principles-or Bible Action Truths. The thirty-seven Bible Action Truths (listed under eight generalprinciples) provide Christians with specific goals fortheir actions and attitudes. Study the Scriptures indicat-ed for a fuller understanding of the principles in BibleAction Truths.

Thousands have found this format helpful in iden-tifying and applying principles of behavior. Yet, thereis no "magic" in this formula. As you study the Word,you likely will find other truths that apply to you. Thekey is for you to study the Scriptures, look for BibleAction Truths, and be sensitive to the leading of theHoly Spirit.1. Salvation-Separation Principle

Salvation results from God's direct action. Al-though man is unable to work for this "gift ofGod," the Christian's reaction to salvation shouldbe to separate himself from the world unto God.a. Understanding Jesus Christ (Matthew 3:17;

16:16; I Corinthians 15:3-4; Philippians 2:9-11) Jesus is the Son of God. He was sent toearth to die on the cross for our sins. He wasburied but rose from the dead after three days.

b. Repentance and faith (Luke 13:3; Isaiah55:7; Acts 5:30-31; Hebrews 11:6; Acts16:31) If we believe that Jesus died for oursins, we can accept Him as our Saviour. Wemust be sorry for our sins, turn from them,confess them to God, and believe that He willforgive us.

c. Separation from the world (John 17:6, 11,14, 18; II Corinthians 6:14-18; I John 2:15-16; James 4:4; Romans 16:17-18; II John 10-11) After we are saved, we should live a dif-ferent life. We should try to be like Christ andnot live like those who are unsaved.

2. Sonship-Servant PrincipleOnly by an act of God the Father could sinful manbecome a son of God. As a son of God, however,

Bible Action Truths

the Christian must realize that he has been' 'boughtwith a price"; he is now Christ's servant.a. Authority (Romans 13:1-7; I Peter 2:13-19;

1 Timothy 6:1-5; Hebrews 13:17; Matthew22:21; 1 Thessalonians 5:12-13) We shouldrespect, honor, and obey those in authorityover us.

b. Servanthood (Philippians 2:7-8; Ephesians6:5-8) Just as Christ was a humble servantwhile He was on earth, we should also behumble and obedient.

c. Faithfulness (l Corinthians 4:2; Matthew25:23; Luke 9:62) We should do our work sothat God and others can depend on us.

d. Goal setting (Proverbs 13:12; 19; Philippians3:13; Colossians 3:2; 1 Corinthians 9:24) Tobe faithful servants, we must set goals for ourwork. We should look forward to finishing ajob and going on to something more.

e. Work (Ephesians 4:28; II Thessalonians3:10-12) God never honors a lazy servant. Hewants us to be busy and dependable workers.

f. Enthusiasm (Colossians 3:23; Romans12:11) We should do all tasks with energyand with a happy, willing spirit.

3. Uniqueness-Unity PrincipleNo one is a mere person; God has created eachindividual a unique being. But because God has anoverall plan for His creation, each unique membermust contribute to the unity of the entire body.a. Self-concept (Psalm 8:3-8; 139; II Corinthi-

ans 5:17; Ephesians 2:10; 4:1-3, 11-13; II Pe-ter 1:10) We are special creatures in God'splan. He has given each of us special abilitiesto use in our lives for Him.

b. Mind (Philippians 2:5; 4:8; II Corinthians10:5; Proverbs 23:7; Luke 6:45; Proverbs4:23; Romans 7:23, 25; Daniel 1:8; James 1:8)We should give our hearts and minds to God.What we do and say really begins in ourminds. We should try to think. of ourselveshumbly as Christ did when He lived on earth.

c. Emotional control (Galatians 5:24; Proverbs16:32; 25:28; II Timothy 1:7; Acts 20:24)With the help of God and the power of theHoly Spirit, we should have control over ourfeelings. We must be careful not to act out ofanger.

d. Body as a temple (I Corinthians 3: 16-17;6: 19-20) We should remember that our bodiesare the dwelling place of God's Holy Spirit.We should keep ourselves pure, honest, anddedicated to God's will.

e. Unity of Christ and the church (John 17:21;Ephesians 2:19-22; 5:23-32; II Thessalonians3:6, 14-15) Since we are saved, we are nowpart of God's family and should unite our-selves with others to worship and grow as

239

Christians. Christ is the head of His church,which includes all believers. He wants us towork together as His church in carrying outHis plans, but He forbids us to work in fel-lowship with disobedient brethren.

4. Holiness-Habit PrincipleBelievers are declared holy as a result of Christ'sfinished action on the cross. Daily holiness of life,however, comes from forming godly habits. AChristian must consciously establish godly patternsof action; he must develop habits of holiness.a. Sowing and reaping (Galatians 6:7-8; Hosea

8:7; Matthew 6:1-8) We must remember thatwe will be rewarded according to the kind ofwork we have done. If we are faithful, we willbe rewarded. If we are unfaithful, we will notbe rewarded. We cannot fool God.

b. Purity (I Thessalonians 4: 1-7; I Peter 1:22)We should try to live lives that are free fromsin. We should keep our minds, words, anddeeds clean and pure.

c. Honesty (II Corinthians 8:21; Romans 12:17;Proverbs 16:8; Ephesians 4:25) We should notlie. We should be honest in every way. Evenif we could gain more by being dishonest, weshould still be honest. God sees all things.

d. Victory (I Corinthians 10:13; Romans 8:37;I John 5:4; John 16:33; I Corinthians 15:57-58) If we constantly try to be pure, honest,and Christ-like, with God's help we will beable to overcome temptations.

S. Love-Life PrincipleWe love God because He first loved us. God'saction of manifesting His love to us through HisSon demonstrates the truth that love must be ex-ercised. Since God acted in love toward us, believ-ers must act likewise by showing godly love toothers.a. Love (I John 3:11, 16-18; 4:7-21; Ephesians

5:2; I Corinthians 13; John 15:17) God's loveto us was the greatest love possible. Weshould, in turn, show our love for others byour words and actions.

b. Giving (II Corinthians 9:6-8; Proverbs 3:9-10; Luke 6:38) We should give cheerfully toGod the first part of all we earn. We shouldalso give to others unselfishly.

c. Evangelism and missions (Psalm 126:5-6;Matthew 28:18-20; Romans 1:16-17; II Co-rinthians 5:11-21) We should be busy tellingothers about the love of God and His plan ofsalvation. We should share in the work offoreign missionaries by our giving andprayers.

d. Communication (Ephesians 4:22-29; Colos-sians 4:6; James 3:2-13; Isaiah 50:4) Weshould have control of our tongues so that we

240

will not say things displeasing to God. Weshould encourage others and be kind and help-ful in what we say.

e. Friendliness (Proverbs 18:24; 17:17; Psalm119:63) We should be friendly to others, andwe should be loyal to those who love andserve God.

6. Communion-Consecration PrincipleBecause sin separates man from God, any com-munion between man and God must be achievedby God's direct action of removing sin. Once com-munion is established, the believer's reactionshould be to maintain a consciousness of this fel-lowship by living a consecrated life.a. Bible study (I Peter 2:2-3; II Timothy 2:15;

Psalm 119) To grow as Christians we mustspend time with God daily by reading HisWord.

b. Prayer (I Chronicles 16:11; I Thessalonians5:17; John 15:7, 16; 16:24; Psalm 145:18;Romans 8:26-27) We should bring all our re-quests to God, trusting Him to answer themin His own way.

c. Spirit-filled (Ephesians 5:18-19; Galatians5:16, 22-23; Romans 8:13-14; I John 1:7-9)We should let the Holy Spirit rule in ourhearts and show us what to say and do. Weshould not say and do just what we want todo, for those things are often wrong and harm-ful to others.

d. Clear conscience (I Timothy 1: 19; Acts24: 16) To be good Christians, we cannot havewrong acts or thoughts or words bothering ourconsciences. We must confess them to Godand to those people against whom we havesinned. We cannot live lives close to God ifwe have guilty consciences.

e. Forgiveness (Ephesians 4:30-32; Luke 17:3-4; Colossians 3:13; Matthew 18:15-17; Mark11:25-26) We must ask forgiveness of Godwhen we have done wrong. Just as God for-gives our sins freely, we should forgive otherswhen they do wrong things to us.

7. Grace-Gratitude PrincipleGrace is unmerited favor. Man does not deserveGod's grace. However, after God bestows Hisgrace, believers should react with an overflow ofgratitude.a. Grace (I Corinthians 15:10; Ephesians 2:8-9)

Without God's grace we would be sinners onour way to hell. He loved us when we did notdeserve His love and provided for us a wayto escape sin's punishment by the death ofHis Son on the cross.

b. Exaltation of Christ (Colossians 1:12-21;Ephesians 1:17-23; Philippians 2:9-11; Gala-tians 6:14; Hebrews 1:2-3; John 1:1-4, 14;5:23) We should realize and remember at all

SCIENCE 4 HTE

times the power, holiness, majesty, and per-fection of Christ, and we should give Him thepraise and glory for everything that is accom-plished through us.

c. Praise (Psalm 107:8; Hebrews 13:15; I Peter2:9; Ephesians 1:6; I Chronicles 16:23-36;29:11-13) Remembering God's great love andgoodness toward us, we should continuallypraise His name.

d. Contentment (Philippians 4: 11; I Timothy6:6-8; Psalm 77:3; Proverbs 15:16; Hebrews13:5) Money, houses, cars, and all things onearth will last only for a little while. God hasgiven us just what He meant for us to have.We should be happy and content with whatwe have, knowing that God will provide forus all that we need. We should also be happywherever God places us.

e. Humility (I Peter 5:5-6; Philippians 2:3-4)We should not be proud and boastful butshould be willing to be quiet and in the back-ground. Our reward will come from God onJudgment Day, and men's praise to us hereon earth will not matter at all. Christ washumble when He lived on earth, and weshould be like Him.

8. Power-Prevailing PrincipleBelievers can prevail only as God gives the power."I can do all things through Christ." God is thesource of our power used in fighting the good fightof faith.a. Faith in God's promises (II Peter 1:4; Phi-

lippians 4:6; Romans 4:16-21; I Thessaloni-ans 5:18; Romans 8:28; 1Peter 5:7; Hebrews3:18-4:11) God always remains true to Hispromises. Believing that He will keep all thepromises in His Word, we should be deter-mined fighters for Him.

b. Faith in the power of the Word of God(Hebrews 4:12; Jeremiah 23:29; Psalm 119;I Peter 1:23-25) God's Word is powerful andendures forever. All other things will passaway, but God's Word shall never pass awaybecause it is written to us from God, and Godis eternal.

c. Fight (Ephesians 6: 11-17; II Timothy 4:7-8;1 Timothy 6:12; I Peter 5:8-9) God does nothave any use for lazy or cowardly fighters.We must work and fight against sin, using theWord of God as our weapon against the Devil.What we do for God now will determine howmuch He will reward us in heaven.

d. Courage (I Chronicles 28:20; Joshua 1:9; He-brews 13:6; Ephesians 3:11-12; Acts 4: 13,31)God has promised us that He will not forsakeus; therefore, we should not be afraid to speakout against sin. We should remember that weare armed with God's strength.

Bible Action Truths

Bible PromisesA. Liberty from Sin-Born into God's spiritual king-

dom, a Christian is enabled to live right and gainvictory over sin through faith in Christ. (Romans8:3-4- "For what the law could not do, in that itwas weak through the flesh, God sending his ownSon in the likeness of sinful flesh, and for sin,condemned sin in the flesh: that the righteousnessof the law might be fulfilled in us, who walk notafter the flesh, but after the Spirit.")

B. Guiltless by the Blood-Cleansed by the blood ofChrist, the Christian is pardoned from the guilt ofhis sins. He does not have to brood or fret over hispast because the Lord has declared him righteous.(Romans 8:33-"Who shall lay any thing to thecharge of God's elect? It is God that justifieth."Isaiah 45:24-"Surely, shall one say, in the Lordhave 1righteousness and strength: even to him shallmen come; and all that are incensed against himshall be ashamed.")

C. Basis for Prayer-Knowing that his righteousnesscomes entirely from Christ and not from himself,the Christian is free to plead the blood of Christand to come before God in prayer at any time.(Romans 5:1-2-"Therefore being justified byfaith, we have peace with God through our LordJesus Christ: by whom also we have access by faithinto this grace wherein we stand, and rejoice inhope of the glory of God.")

D. Identified in Christ-The Christian has the assur-ance that God sees him as a son of God, perfectlyunited with Christ. He also knows that he has ac-cess to the strength and the grace of Christ in hisdaily living. (Galatians 2:20-' 'I am crucified withChrist: nevertheless, 1 live; yet not I, but Christliveth in me: and the life which I now live in theflesh I live by the faith of the Son of God, wholoved me, and gave himself for me." Ephesians1:3- "Blessed be the God and Father of our LordJesus Christ, who hath blessed us with all spiritualblessings in heavenly places in Christ.")

E. Christ as Sacrifice-Christ was a willing sacrificefor the sins of the world. His blood covers everysin of the believer and pardons the Christian foreternity. The purpose of His death and resurrectionwas to redeem a people to Himself. (Isaiah 53:4-5-" Surely he hath borne our griefs, and carriedour sorrows: yet we did esteem him stricken, smit-ten of God, and afflicted. But he was wounded forour transgressions, he was bruised for our iniqui-ties: the chastisement of our peace was upon him;and with his stripes we are healed." John 10:27-28- "My sheep hear my voice, and I know them,and they follow me: and I give unto them eternal

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life; and they shall never perish, neither shall anyman pluck them out of my hand.")

F. Christ as Intercessor-Having pardoned themthrough His blood, Christ performs the office ofHigh Priest in praying for His people. (Hebrews7:25-"Wherefore he is able also to save them tothe uttermost that come unto God by him, seeinghe ever liveth to make intercession for them." John17:20- "Neither pray I for these alone, but forthem also which shall believe on me through theirword.")

G. Christ as Friend-In giving salvation to the be-liever, Christ enters a personal, loving relationshipwith the Christian that cannot be ended. This re-lationship is understood and enjoyed on the believ-er's part through fellowship with the Lord throughBible reading and prayer. (Isaiah 54:5-' 'For thyMaker is thine husband; the Lord of hosts is hisname; and thy Redeemer the Holy One of Israel;The God of the whole earth shall he be called."Romans 8:38-39- "For I am persuaded, that nei-ther death, nor life, nor angels, nor principalities,nor powers, nor things present, nor things to come,nor height, nor depth, nor any other creature, shallbe able to separate us from the love of God, whichis in Christ Jesus our Lord.")

H. God as Father-God has appointed Himself to beresponsible for the well-being of the Christian. Heboth protects and nourishes the believer, and it wasfrom Him that salvation originated. (Isaiah 54: 17-"No weapon that is formed against thee shall pros-per; and every tongue that shall rise against theein judgment thou shalt condemn. This is the heri-tage of the servants of the Lord, and their right-eousness is of me, saith the Lord." Psalm 103:13-"Like as a father pitieth his children, so the Lordpitieth them that fear him.")

I. God as Master-God is sovereign over all crea-tion. He orders the lives of His people for His gloryand their good. (Romans 8:28-" And we know thatall things work together for good to them that loveGod, to them who are the called according to hispurpose.' ')

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