Addition of Three or More Numbers - Everyday Math - Login€¦ · 31 16 102 122 107 127 109 112 117 132? 12 19 + 19 = 31 EM3MJ1_G2_U06_131_158.indd 133 1/29/11 10:57 AM Math Journal

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eToolkitePresentations Interactive Teacher’s

Lesson Guide

Algorithms Practice

EM FactsWorkshopGame™

AssessmentManagement

Family Letters

CurriculumFocal Points

Common Core State Standards

378 Unit 6 Whole-Number Operations and Number Stories

Advance Preparation

Teacher’s Reference Manual, Grades 1–3 pp. 78, 79, 82–89

Addition of Threeor More Numbers

Objective To review strategies for solving addition problems,

with emphasis on problems having three or more addends.w

Key Concepts and Skills• Use and explain strategies for adding

three or more numbers.

[Operations and Computation Goal 2]

• Write number models with three or

more numbers.

[Patterns, Functions, and Algebra Goal 2]

• Describe and apply the associative

property of addition.

[Patterns, Functions, and Algebra Goal 3]

Key ActivitiesChildren review strategies for solving

addition problems. They identify the easiest

order in which to add three numbers, write

number models, and practice adding three or

more 1-digit and 2-digit numbers.

Ongoing Assessment: Recognizing Student Achievement Use journal page 131. [Operations and Computation Goal 2]

MaterialsMath Journal 1, p. 131

Math Masters, p. 473 (optional)

per partnership: 4 each of number cards

0–20 (from the Everything Math Deck, if

available) � calculator (optional)

Practicing Estimation and the Partial-Sums AlgorithmMath Journal 1, p. 132

Children estimate sums and use

the partial-sums algorithm to find

exact sums.

Math Boxes 6�1Math Journal 1, p. 133

Children practice and maintain skills

through Math Box problems.

Home Link 6�1Math Masters, pp. 156 and 157

Children practice and maintain skills

through Home Link activities.

READINESS

Finding Sums of 10 Using a Ten Frame CardMath Masters, p. 422

per group: 1 each of number cards 1–10

(from the Everything Math Deck, if available),

10 blue counters, 10 red counters, blue and

red crayons, one half-sheet of paper

Children use ten frames to practice with

sums of 10.

ENRICHMENTAdding with Four or More AddendsMath Masters, p. 158

Children create number sentences using four

or more addends.

Teaching the Lesson Ongoing Learning & Practice Differentiation Options

��

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Lesson 6�1 379

Unit

pencils

1 Teaching the Lesson

� Math Message Follow-Up WHOLE-CLASS ACTIVITY

Review strategies for solving addition problems.

Draw a unit box on the board. Ask: What is the Math Message story about? Sample answer: Finding the total number of pencils three children have What label should go in the unit box? pencils

Getting Started

Math Message(Use names of children in your class.)

Lia has 13 pencils. Thomas has 6 pencils. Nate has 7. How many pencils do they have in all? 26 pencils

Mental Math and Reflexes Pose addition and subtraction problems that feature multiples of 10. Suggestions:

70 + 20 = ? 90

? = 20 + 8 28

70 - 20 = ? 50

80 + 15 = ? 95

65 - 5 = ? 60

? = 70 + 13 83

89 - 49 = ? 40

? = 69 + 11 80

75 - 15 = ? 60

Interactive whiteboard-ready

ePresentations are available at

www.everydaymathonline.com to

help you teach the lesson.

Invite children to share strategies for solving the Math Message problem. Encourage them to doodle or calculate with a pencil and paper if they need to. Suggestions:

� Use counters, fingers, or the number grid as an aid for counting up.

� Draw pictures or use tally marks. (See margin.)

� Use a parts-and-total diagram. (See margin.)

� Solve by mental arithmetic.

� Use the partial-sums method. (See margin.)

� Draw an open number line. (See margin.)

� Adding Three Numbers WHOLE-CLASS ACTIVITY

in Any OrderWrite number models for the Math Message problem in horizontal format. Then ask:

● Does it make a difference in what order the sums are added? no

● Which order makes it easiest to find the sum?

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NOTE A calculator is a good tool to show

how adding in different orders gives the same

sum. Use of the calculator will also

demonstrate that when adding more than two

numbers, it is not necessary to enter that

sum and the third number as a new problem.

NOTE The Associative Property of Addition

says that when you add three numbers it

doesn’t matter which two are added first. In

this lesson, children are using this property

but do not expect them to use the term.

Three Addends Record SheetLESSON

6 �1

Date Time

For each turn:

� Write the 3 numbers.

� Add the numbers.

� Write a number model to show the order in which you added.

1. Numbers: , , 2. Numbers: , , Number model: Number model:

+ + = + + =


+ + = + + =


+ + = + + =

For Problems 7 and 8, use 4 numbers.

7. Numbers: , , , Number model: + + + =


Numbers and number models vary.

�

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Math Journal 1, p. 131

Student Page

Option 1

Add 13 and 6 first to make 19; 13 + 6 + 7 =∨

then add 7. 19 + 7 = 26

Option 2

Add 13 and 7 first to make 20; 13 + 7 + 6 = ∨

then add 6. 20 + 6 = 26

Option 3

Add 6 and 7 first to make 13; 6 + 7 + 13 =∨

then double 13. 13 + 13 = 26

Write three or four numbers on the board and ask children to decide which order makes it easiest for them to find the sum.Repeat with other sets of numbers. Suggestions:

Encourage children to make up similar problems for the class to solve. Some number sets (for example, 7, 9, and 17) do not have an easiest order for addition.

Summary: Three or more numbers can be added in any order. Also, they can often be ordered in a way that makes it easier to find the sum.

� Playing Three Addends PARTNER ACTIVITY

(Math Journal 1, p. 131; Math Masters, p. 473)

Tell children they will work with a partner to practice adding three or four numbers using 4 each of number cards 0–20 from the Everything Math Deck.

Select two children to demonstrate the game.

Directions

1. Shuffle the cards. Place the deck number-side down between the two players.

2. One player turns over the top 3 cards. Each partner writes the 3 numbers on a Record Sheet.

3. Partners add the numbers, writing a number model to show the order in which they added.

4. Partners compare their answers.

PROBLEMBBBBBBBBBBBOOOOOOOOOOBBBBBBBBBBBBBBBBBBBBBBBBB MMMMEEEEMLBLELBLEBLELLLBLEBLEBLEBLEBLEBLEBLEEEEMMMMMMMMMMMMMOOOOOOOOOOOOBBBBBLBLBBLBLBLLBLLLLPROPROPROPROPROPROPROPROPROPROPROPRPRPROPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPROROOROROROOROOPPPPPPP MMMMMMMMMMMMMMMMMMMEEEEEEEEEEEELLELEEEEEEEEEELLLLLLLLLLLLLLLLLLLLRRRRRRRRRRRRRRRRRPROBLEMSOLVING

BBBBBBBBBBBBBBBBBBBB EEELEMMMMMMMMOOOOOOOOOBBBLBLBLBLBLBROOOOROROROROROROROROROO LELELELEEEEEELEMMMMMMMMMMMMLEMLLLLLLLLLLLLLLLLLLLLRRRRRRRRRRRGGGGGLLLLLLLLLLLLVINVINVINVINVINNNNVINVINVVINVINVINVINGGGGGGGGGGGOLOOLOLOLOLOLOLOOO VINVINVLLLLLLLLLLVINVINVINVINNVINVINVINVINVINVINVINVINNGGGGGGGGGGOOOLOLOLOLOLLOOO VVVLLLLLLLLLLLVVVVVVVVVVVSOSOSOOSOSOSOSOSOSOOSOSOSOOOOSOOSOSOSOSOSOSOSOOSOOSOSOSOSOSOSOSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS VVVVVVVVVVVVVVVVVVVVVVVLLLLLLLVVVVVVVVVLLLVVVVVVVVLLLLLLLVVVVVLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLSSSSSSSSSSSSSSSSSSSSS GGGGGGGGGGGGGGGGGGOOOOOOOOOOOOOOOOOO GGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGNNNNNNNNNNNNNNNNNNNNNNNNNNNNIIIIIIIIIIIIIIIIIIIISOLVING

� 14, 5, 6

� 7, 25, 25

� 9, 14, 11, 6

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Lesson 6�1 381

Math BoxesLESSON

6 �1

Date Time

1. Which is least likely to happen? Choose the best answer.

A dog will have puppies today.

You will go to sleep tonight.

Chocolate milk will come out of the water fountain.

Someone will read you a book.

3. Arlie harvested 12 bushels of corn and 19 bushels of tomatoes. How many bushels in

all? bushels

Fill in the diagram and write a number model.

6. Use your calculator. Start at 92.

Count by 5s.

92, 97, , , ,

, , ,

2. How long is this line segment?

about cm

5. Put these numbers in order from least to greatest and circle the middle number (the median).

109, 99, 129

6

109

4. How many dots in this 2-by-8 array?

7

3116

102122

10712712910999

112132117

?

12 1912 + 19 = 31

EM3MJ1_G2_U06_131_158.indd 133 1/29/11 10:57 AM


Student Page

Fill in the unit box. Then, for each problem:

� Make a ballpark estimate.

� Write a number model for your estimate. Then solve the problem. For Problems 1, 2, and 3 use the Partial-Sums Algorithm. For Problems 4–6, use any strategy you choose.

� Compare your estimate to your answer.

1. Ballpark 2. Ballpark 3. Ballparkestimate: estimate: estimate:

29 + 7 = 87 + 9 = 37 + 42 =

4. Ballpark 5. Ballpark 6. Ballparkestimate: estimate: estimate:

27 + 13 = 138 + 46 = 142 + 128 =

Ballpark EstimatesLESSON

6 �1

Date Time

Unit

30 + 10 = 40

30 + 10 = 40

90 + 10 = 100

140 + 50 = 190

40 + 40 = 8036

40

96

184

79

270140 + 130 = 270

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Student Page

Have partners record their numbers and number models on journal page 131 for eight rounds of the game. Problems 7 and 8 involve adding four numbers. Children may use Math Masters, page 473 to record additional numbers and number models.

Ongoing Assessment: Journal

Page 131 �Recognizing Student Achievement

Use journal page 131 to assess children’s ability to add three and four numbers.

Children are making adequate progress if they can correctly add the three

and four numbers using manipulatives. Some children may be able to add the

numbers mentally while others may be able to order the numbers in a way that

makes it easier to find the sum.

[Operations and Computation Goal 2]

2 Ongoing Learning & Practice

� Practicing Estimation and INDEPENDENTACTIVITY

the Partial-Sums Algorithm(Math Journal 1, p. 132)

Review the instructions for the journal page with children. Have them begin by making a ballpark estimate for each sum. Children then use the partial-sums algorithm in Problems 1–3 to find the exact sum. Children use any strategy they choose for Problems 4–6.

� Math Boxes 6�1 INDEPENDENTACTIVITY

(Math Journal 1, p. 133)

Mixed Practice Math Boxes in this lesson are linked with Math Boxes in Lessons 6-3 and 6-5. The skills in Problems 5 and 6 preview Unit 7 content.

Adjusting the ActivityVariations on the Three Addends game:

� Children use triplets with 2- or 3-digit numbers. For example, 140 + 150 + 60 350

� Children draw 4 cards at each turn and solve problems with 4 addends.

� Children use a calculator to solve the problems.

A U D I T O R Y � K I N E S T H E T I C � T A C T I L E � V I S U A L

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Add. Use the partial-sums method.

Example: 33 42 + 11Add the tens. → (30 + 40 + 10) → 80Add the ones. → (3 + 2 + 1) → 6Add the partial sums. → (80 + 6) → 86

Name Date Time

HOME LINK

6�1 Adding Three or More Numbers continued

5. 6. 7.

8. 9. 10. 14 9 85 + 96 180 24204

Practice

14 29 + 27 50 20 70

8 19 + 35 40 22 62

46 25 + 12 70 13 83

23 32 + 14 60 9 69

21 40 45 + 63 160 9 169

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Math Masters, p. 157

Home Link Master

Name Date Time

Sometimes the order in which you add numbers can make it easier to find the sum. For example, when adding 17, 19, and 23, some people may first calculate 17 + 23, which equals 40, and then add 19 (40 + 19 = 59). For Problems 1– 4, help your child look for easy combinations. Before working on Problems 5–10, you might go over the example with your child.

Please return this Home Link to school tomorrow.

For each problem: Sample number models shown. � Think about an easy way to add the numbers.

� Write a number model to show the order in which you are adding the numbers.

� Find each sum. Tell someone at home why you added the numbers in that order.

HOME LINK

6�1 Adding Three or More Numbers

1. 13

6 7

Number model:

13 + 7 + 6 = 26

3.

915

25

Number model:

15 + 25 + 9 = 49

2. 822

5

Number model:

8 + 22 + 5 = 35

4.

629

114

Number model:

29 + 11 + 6 + 4 = 50

Family Note

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Home Link Master

Name Date Time

Ten-Frame Card

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Teaching Aid Master

� Home Link 6�1 INDEPENDENTACTIVITY

(Math Masters, pp. 156 and 157)

Home Connection Children practice adding three and four numbers in the easiest order. Children also practice using the partial-sums method for adding three and four numbers.

3 Differentiation Options

READINESS SMALL-GROUP ACTIVITY

� Finding Sums of 10 Using a 5–15 Min

Ten Frame Card(Math Masters, p. 422)

To provide experience with sums of 10, have children solve addition problems using a ten frame card. Children mix up the number cards and put them facedown on the table. They draw a number card and put that many blue counters on their ten-frame card. They predict how many counters they need to fill the ten-frame card. They check their predictions by placing red counters in the remaining squares. On a half-sheet of paper, they record the dot pattern in their ten-frame card using blue and red crayons, and they write the number sentence for how they got to ten. Have children explain their number sentences; for example, “I started with 6 blue counters and added 4 red counters to get 10 counters total.”


For each sum, write a number sentence using four or moreaddends. Each number sentence must include a double and atleast one pair of addends that equal ten.

43 62

79 112

LESSON

6�1

Name Date Time

Addition with Several Addends

Sample answer:6 � 4 � 15 � 15 � 3� 43

Sample answer:8 � 2 � 26 � 26 � 62

Sample answer:7 � 3 � 33 � 33 � 3� 79

Sample answer:9 � 1 � 51 � 51 � 112


Teaching Master

Lesson 6�1 383

ENRICHMENT INDEPENDENTACTIVITY

� Adding with Four or 15–30 Min

More Addends(Math Masters, p. 158)

To further explore children’s knowledge of number facts, number sense, and problem solving, have children create number sentences using four or more addends with Math Masters, page 158. Within each number sentence, they must include a double and at least one pair of addends whose sum is ten; for example, 37 = 10 + 10 + 7 + 6 + 4. Have children explain the strategies they use to add the numbers.


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156

Name Date Time

Sometimes the order in which you add numbers can make it easier to find the sum. For example, when adding 17, 19, and 23, some people may first calculate 17 + 23, which equals 40, and then add 19 (40 + 19 = 59). For Problems 1– 4, help your child look for easy combinations. Before working on Problems 5–10, you might go over the example with your child.

Please return this Home Link to school tomorrow.

For each problem:

� Think about an easy way to add the numbers.

� Write a number model to show the order in which you are adding the numbers.

� Find each sum. Tell someone at home why you added the numbers in that order.

HOME LINK

6�1 Adding Three or More Numbers

1. 13

6 7

Number model:

+ + =

3.

915

25

Number model:

+ + =

2. 822

5

Number model:

+ + =

4.

629

114

Number model:

+ + + =

Family Note

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Copyright

© W

right

Gro

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Add. Use the partial-sums method.

Example: 33 42 + 11Add the tens. → (30 + 40 + 10) → 80Add the ones. → (3 + 2 + 1) → 6Add the partial sums. → (80 + 6) → 86

157

Name Date Time

HOME LINK

6�1 Adding Three or More Numbers continued

5. 6. 7.

8. 9. 10. 14 9 85 + 96

Practice

14 29 + 27

8 19 + 35

46 25 + 12

23 32 + 14

21 40 45 + 63


Copyright

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right

Gro

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473

For each turn:

� Write the 3 numbers.

� Add the numbers.

� Write a number model to show the order in which you added.

1. Numbers: , , 2. Numbers: , ,

Number model: Number model:

+ + = + + =



+ + = + + =



+ + = + + =

For Problems 7 and 8, use 4 numbers.



Name Date Time

1

3

2

4Three Addends Record Sheet


Documents

Addition of Three or More Numbers - Everyday Math - Login€¦ · 31 16 102 122 107 127 109 112 117 132? 12 19 + 19 = 31 EM3MJ1_G2_U06_131_158.indd 133 1/29/11 10:57 AM Math Journal