Rationale Objectivesdata.cteunt.org/content/files/law/forensic-science/unit-1-safety... · Use the Find the Scientific Method Teacher’s Notes to guide ... The study of natural phenomena

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Scientific Method

Course Forensic Science Unit I Understanding the Scientific Method Essential Question How are the basics of science used in forensics? TEKS §130.295(c) (2)(A–E) Prior Student Learning Lab Safety Estimated Time 5 hours total

1 hr. lecture

3 hrs. activities

1 hr. quizzes and exam

Rationale Forensics is an actual application of science and technology to solve crimes in the criminal justice system. Since forensics employs a vast number of scientific fields, knowing the strengths and limitations of scientific theories and hypotheses, and understanding the scientific method is crucial to using science to its full potential in the pursuit of justice. Objectives The student will be able to:

1. Define science and the scientific method. 2. Differentiate between scientific hypotheses and scientific theories. 3. Explain how the scientific method is used to answer questions and

solve cases in forensics. 4. Use the scientific method to solve an investigation, including all the

steps of the method and an experiment. Engage Show students an episode of the television show that illustrates the scientific method. Ask the students to try and find the steps of the scientific method using the Find the Scientific Method Handout, and discuss their results as a class. Use the Find the Scientific Method Teacher’s Notes to guide the discussion, and use the Discussion Rubric for assessment. Key Points I. Science – modern science tries to understand and explain how the

natural world works now and how it got to be that way A. Facts about science

1. The study of natural phenomena 2. Studies what can be observed, measured, and tested by

scientific methods 3. We must use our senses to observe and evaluate 4. Based on the assumption that the universe is orderly,

reasonable, and testable 5. Used to predict natural events that may occur 6. Based on physical, mathematical, and conceptual models 7. Classified into many different fields, topics, or categories for

specialized study 8. The different fields overlap and depend on each other for further

knowledge and explanations 9. A vast body of knowledge that is always changing and

expanding, but is does have limitations 10. Objective, unbiased, and impartial—or it should be

B. Myths about science 1. A rigid collection of facts that are inflexible 2. Able to explain the answer to every question (some phenomena

are not scientifically testable) 3. Unorganized, unrelated, or untestable 4. Based on that which cannot be observed or measured, or that

which is outside of our senses to be perceived


5. Only based on one disciple, field, or topic of knowledge 6. Subjective, biased, or partial (it should not be)

C. Scientific Explanations – Hypothesis, Theory, or Law 1. Hypothesis – an educated guess based on observation

a) Can be given as an explanation for the occurrence of an event or a presumption to guide an investigation

b) Should be based on some knowledge or research c) Must try to answer a scientific question d) Must be testable by known scientific methods e) Can be supported or refuted through further observation or

experimentation f) Can be proven wrong; it doesn’t have to be right

(1) A wrong hypothesis only leads to another hypothesis (2) A better product, a better clue, a better suspect

g) Should be stated in such a way that the experiment will collect measureable/quantifiable data if possible

2. Theory – summarizes a hypothesis or group of hypotheses that have been supported with repeated testing over a wide variety of conditions over time

a) Are valid as long as no evidence disputes them b) Are well-established and highly reliable c) Can be used as principles of explanation and prediction for

a group of phenomena d) Can be disproven, modified, or changed with new scientific

knowledge, observations, and technology 3. Law – generalizes a body of observations that can be used to

describe or predict something universally understood in nature a) At the time that it is made, no exceptions can have ever

been found in a law b) Laws never explain “why” something happens, only that it

will always happen the same way with no exceptions c) Example – Newton’s Law of Gravity could be used to

predict the behavior of a dropped object, but it could not explain why it happened

d) Theories explain “why” something happens; laws predict that it will always happen the same way

D. Six Criteria of Science: CONPTT 1. Consistent – results are based on repeatable observations

and/or explanations 2. Observable – limited to the basic human senses or extensions

of the senses (microscopes, computers, etc.) 3. Natural – a natural cause must be used to explain why or how;

supernatural explanations are not allowed 4. Predictable – the result or observation can be used to make

predictions about natural events 5. Testable – the natural cause of the event must be testable

through the process of science and/or controlled experiments 6. Tentative – theories are subject to revision and correction, even

to the point that the entire theory might be proven wrong E. Non-Science – an area of science that does not meet the criteria of

science or CONPTT


1. Such areas may be very logical and based on good reasoning, but do not fall into the true realm of science

2. Examples: a belief system (religious), philosophy, personal opinion, ethic, or sense of aesthetics

II. Scientific Method – the established method of research and discovery. It

follows an eight-step process to collect and evaluate information, and maintain objectivity when arriving at the conclusion. It is used to solve every case in the criminal justice system

A. General Steps of the Scientific Method 1. Asking or defining a question – start with a question that can be

tested a) The question should be specific b) It can be based on observations c) Information is normally gathered before the final question

is decided 2. Researching the question or problem – books, journal articles,

manuals, magazines, newspapers, the internet, etc. are used in the research

a) The hypothesis may have been already studied or researched (there may already be an answer)

b) Research sources used should be scientific, objective, and unbiased

3. Forming a hypothesis – the answer to the question is given in the form of an educated guess of what is expected to happen or the answer

a) The hypothesis must be in the form of a statement b) The hypothesis must be researched before it’s stated (that

is why it is an educated guess) c) The hypothesis must be testable; if it is not, it is not a valid

hypothesis d) The hypothesis must allow for a variable to be tested and

what results are expected e) Should be given in this format: “If this________ is

done/changed, then this_______ will happen/be observed” f) Null hypothesis – what the researcher is seeking to not

have happen, to disprove, or to nullify (sometimes given in addition to the hypothesis)

(1) The opposite of the hypothesis

4. Developing and performing the experiment a) Must test the hypothesis b) Should have planned steps for implementation c) Should only have one variable that is tested d) Either supports or disproves the hypothesis e) The experiment will be retested to validate the results

5. Collecting the data – a lab notebook is kept through all of the steps of the scientific method

a) All observations that led to the question should be recorded, as should the research that was done, the formation of the hypothesis, and any hypotheses that were not used


b) Write down how the experiment was designed and all its steps

c) All the details, data, and measurements of the experiment are documented

(1) Document every detail (2) Write down any mistakes or changes (3) Leave nothing out

d) Clearly labeled tables are normally used to document data, especially changes over time (this makes graphing data easier later)

6. Analyzing the data – data collected is scrutinized a) Information is compared and contrasted b) Graphs, tables, and charts are used to visually review the

data c) Averages, means, and deviations should be calculated;

statistical analyses should also be performed 7. Writing the conclusion – data/results are studied to draw

conclusions a) It is stated whether the results support or disprove the

hypothesis (it is perfectly okay for the hypothesis to be incorrect)

b) Any additional data found, or new results established that were unexpected, might need research to be explained

c) All problems or sources of error should be discussed d) Results should be interpreted without any bias or

prejudice, and as objectively as possible e) Any future data or experiments that are needed for further

information should be considered f) The results gathered should be repeatable by others

8. Communicating the results – the results are communicated and published in written format in a scientific journal

a) Lecturing, sharing, and retesting are performed b) The format used for communicating depends on the

actually topic studied and the type of audience who will be reviewing/using the scientific research

B. Scientific Method Intersections 1. There are many crossovers, turnarounds, and repeats in the

scientific method; it is seldom that the method proceeds through all eight steps in an organized fashion

2. This is especially true in criminal investigations: research yields more knowledge that changes the hypothesis and the experiment (investigation), more data is collected that also might change the hypothesis, the exploration changes, results are not expected, conclusions can change, and the process may begin again

C. Experiments 1. Experimental design – the experiment should be well-designed

and meet certain criteria a) The experiment should be based on the research that was

done in forming the question and the hypothesis b) All steps and conditions for the experiment should be


planned and detailed c) Steps should be recorded before the experiment, and a

record made of any changes made during or after the experiment

d) The experiment should be designed, carried out, and recorded in such a way that further investigators can repeat the procedure (and hopefully get the same results)

e) All variables should be organized and managed f) Technology use should be planned g) Data collection should be done with extreme care and

answer the following questions (1) How will data be collected? (2) Will data collection be reliable? (3) How can data be measured, and quantitative and

objective? (4) Is data subject to bias in any step? (5) Will data collection be precise and accurate?

h) The method of recording data collection should also be premeditated

i) The experiment should be planned so that the hypothesis made is tested and the original question is answered

j) The experiment should be conducted several times before results are published and communicated

2. Variable – anything that can be changed or controlled in an experiment, and/or any changes that occur because of something else that changed

a) Three types of variables (1) Independent variable

(a) The one factor that is changed, or the one factor that is different between the groups

(b) One factor is best, so you can depend on your results, but in analyzing a criminal case all of the variables cannot always be controlled or minimized

(2) Dependent variable (a) The variable that is observed to see whether it is

affected by the independent variable (b) This is normally the data that is collected as the

experiment progresses (c) The dependent variable depends on what was

changed in the experiment, or it depends on the independent variable

(3) Controlled variables (often called constants or controls)

(a) Things that could change in the experiment, but should be kept constant or unchanging

(b) If these change you have more than one independent variable and your data collected or results may not be valid

b) Example – in an experiment comparing the fizz released from different types of soda your variables are

http://en.wikipedia.org/wiki/Dependent_and_independent_variables

http://en.wikipedia.org/wiki/Dependent_and_independent_variables


(1) Independent variable – the type of sodas tested (this should be the only difference between the sodas)

(2) Dependent variable – the amount of fizz released (3) Controlled variables

(a) Same size/type of soda cans (b) Bought at the same store, with the same

expiration dates (c) Kept at the same temperature, with the same

amount of agitation per can (d) The same method of measuring fizz volume

should be used III. Contribution of Science

A. Science and the scientific method are an integral part of mankind and have been for many years

B. Explaining the natural world around us is a quest that many share C. The scientific method is our way of consistently answering questions

and creating new inspiration D. Scientific ideas have limitations and can evolve over time, but

scientific knowledge is the most reliable knowledge we have about the natural world

E. The criminal justice system has been tremendously impacted by the use of the scientific method and scientific knowledge, and science is the basis of the field of Forensics

Activities 1. Choosing the Right Equipment. Have the students select tool(s) for the

hypothesis on the Choosing the Right Equipment Worksheet. Have students discuss their answers as a class. Use the Choosing the Right Equipment Worksheet Key and/or the Discussion Rubric for assessment.

2. Bikini Bottom Experiments. Have the students complete some simple experiments. The experiments and answer keys at http://sciencespot.net/Media/scimthdexps.pdf may be used.

3. Designing Experiments. Have the students read the scenario and answer the questions on the Designing Experiments Handout. Use the Designing Experiments Key for assessment.

4. Purchase Power. Have the students select an everyday product and test it with their own experiment using the Purchase Power Handout as a guide. Use the Purchase Power Checklist for assessment.

Assessments Scientific Method Exam Scientific Method Quiz Choosing the Right Equipment Worksheet Key Purchase Power Checklist Scientific Method Crossword Puzzle Key Discussion Rubric

http://sciencespot.net/Media/scimthdexps.pdf


Presentation Rubric Research Rubric Materials Scientific Method computer-based presentation Choosing the Right Equipment Worksheet and Key Designing Experiments Handout and Key Purchase Power Handout and Checklist Scientific Method Crossword Puzzle and Key Expanding to Real Life Handout Laser projector Computer Worksheets Computer Lab or Internet Sources Resources Saferstein, Richard. Forensic Science: An Introduction. New Jersey:

Pearson Prentice Hall, 2008. Bertino, Anthony J. Forensic Science: Fundamentals & Investigations.

Mason, OH: South-Western Cengage Learning, 2009. Deslich, Barbara; Funkhouse, John. Forensic Science for High School

Dubuque, Iowa: Kendall/Hunt Publishing Company, 2006. http://sciencespot.net/Media/scimthdexps.pdf Accommodations for Learning Differences For reinforcement, have students practice vocabulary by completing the Scientific Method Crossword Puzzle. Use the Scientific Method Crossword Puzzle Key for assessment. For enrichment, have students research, summarize, and present an article related to science. Use the Expanding to Real Life Handout for the activity, and the Research Rubric and Presentation Rubric for assessment. State Education Standards Texas Essential Knowledge and Skills for Career and Technical Education §130.295. Forensic Science (One Credit).

(2) The student uses scientific methods and equipment during laboratory and field investigations. The student is expected to: (A) know the definition of science and understand that it has

limitations, as specified in subsection (b)(2) of this section;

(B) know that scientific hypotheses are tentative and testable statements that must be capable of being supported or not supported by observational evidence. Hypotheses of durable explanatory power which have been tested over a wide variety of conditions are incorporated into theories;

(C) know scientific theories are based on natural and physical phenomena and are capable of being tested by multiple independent researchers. Unlike hypotheses, scientific theories are well-established and highly-

http://sciencespot.net/Media/scimthdexps.pdf


reliable explanations, but they may be subject to change as new areas of science and new technologies are developed;

(D) distinguish between scientific hypotheses and scientific theories;

(E) plan and implement descriptive, comparative, and experimental investigations, including asking questions, formulating testable hypotheses, and selecting equipment and technology;

College and Career Readiness Standards I. Nature of Science: Scientific Ways of Learning and Thinking

A. Cognitive skills in science 1. Utilize skepticism, logic, and professional ethics in science.

B. Scientific inquiry 1. Design and conduct scientific investigations in which hypotheses are formulated and tested.


Name________________________________ Date______________________

Scientific Method Exam

Multiple Choice

_____1. The first step in the scientific method is a. Making observations b. Conducting experiments c. Analyzing data d. Defining the problem/asking the question

_____2. To gather information, we can a. Read books b. Ask questions c. Use our senses to study things d. All of the above

_____3. When we make an educated guess we are forming a. Data b. A hypothesis c. Variables d. A factor

_____4. Our recorded observations are called a. Data b. Control factors c. Hypotheses d. Experiments

_____5. At the end of the scientific method, we must state a a. Purpose b. Question c. Hypothesis d. Conclusion

_____6. Every experiment must have only one a. Variable b. Step c. Measurement d. Object

True or False (T or F)

_____7. The first step of the scientific process is testing the hypothesis.

_____8. Sometimes, steps of the scientific process must be repeated.

_____9. Every experiment should have at least three experimental factors or variables.

_____10. A control group is a factor that is missing the variable, but is the same as other factors in every other way.

_____11. Written observations made while using the scientific process are known as data.

_____12. A theory is a hypothesis that has not yet been tested.

_____13. Measurements must be made carefully to make sure all factors, except the variable, are the same.


Scientific Method Exam Key

1. D 2. D 3. B 4. A 5. D 6. A 7. F 8. T 9. F 10. T 11. T 12. F 13. T


Name________________________________ Date______________________

Scientific Method Quiz

Matching

1. ____ An educated guess

2. ____ Factor in an experiment that is missing the variable but is the same as other factors in every other way

3. ____ Written or recorded observations made while using the scientific method

4. ____ Step-by-step process that scientists have developed to help them solve problems and test new ideas

5. ____ A hypothesis that has been tested many times and is supported by data

6. ____ Factor being tested; the one factor that is different from all others in an experiment

7. ____ An activity or group of activities performed to test a hypothesis

8. ____ Final statement made after an experiment to prove or disprove the hypothesis

A. Scientific Method

B. Single Variable

C. Control

D. Hypothesis

E. Experiment

F. Data

G. Theory

H. Conclusion


Fill-in-the-blank: Read the following paragraph, and circle the word that best fills each blank. The ___9___ method is a process that scientists use to help them test new ideas. The first step in the process is defining the ___10___ . Next, information must be gathered using one of more of the five ___11___ . The scientist then makes an educated guess or a ___12___ . This is tested by performing one or more activities called ___13___ . Observations are made and recorded. The recorded observations are known as ___14___ . After analyzing the data, the scientist comes to a ___15___ that either proves or disproves the hypothesis. When a hypothesis is tested many times and supported, it becomes known as a___16___.

9. 13.

A. Variable A. Theories

B. Scientific B. Experiments

C. Control C. Properties

D. Biological D. None of the above

10. 14.

A. Conclusion A. Data

B. Data B. Hypotheses

C. Experiment C. Structures

D. Problem/question D. Expressions

11. 15.

A. Senses A. Meeting

B. Controls B. Consideration

C. Solutions C. Laboratory

D. Solvents D. Conclusion

12. 16.

A. Variable A. Solvent

B. Factor B. Control

C. Hypothesis C. Deduction

D. Consideration D. Theory


Scientific Method Quiz Key

1. D

2. C

3. F

4. A

5. G

6. B

7. E

8. H

9. B

10. D

11. A

12. C

13. B

14. A

15. D

16. D


Name________________________________ Date______________________

Scientific Method Crossword Puzzle

Across 1. Anything that can be changed or controlled in an experiment, and/or any changes that occur because of

something that did change 3. The study of natural phenomena 4. An educated guess based on observation 6. The first step of the scientific method is to have one of these 8. Results are based on repeatable observations and/or explanations 10. Scientists use their data to make charts and what to communicate the results of an experiment? 13. Theories are subject to revision and correction, even to the point of the entire theory being proven wrong 14. Can be used as principles of explanation and prediction for a group of phenomenon Down 2. After scientists make a hypothesis, they perform what to collect data? 5. Scientists write this after an experiment to summarize it and its results 7. The natural cause of the event must be 9. This kind of variable is the part of the experiment that is affected by the independent variable 11. Is the part of an experiment that is not being tested and is used for comparison 12. At the time that it is made, no exceptions have ever been found to this


Scientific Method Crossword Puzzle Key

Across 1. Variable – anything that can be changed or controlled in an experiment, and/or any changes

that occur because of something that did change 3. Science – the study of natural phenomena 4. Hypothesis – an educated guess, based on observation 6. Question – the first step of the scientific method is to have one of these 8. Consistent – results are based on repeatable observations and/or explanations 10. Graphs – scientists use their data to make charts and what to communicate the results of an

experiment 13. Tentative – theories are subject to revision and correction, even to the point of the entire

theory being proven wrong 14. Theory – can be used as principles of explanation and prediction for a group of

phenomenon Down 2. Experiment – after the scientist makes a hypothesis, they perform a what to collect data 5. Conclusion – scientists write this after an experiment to summarize it and its results 7. Testable – the natural cause of the event must be 9. Dependent – this kind of variable is the part of the experiment that is affected by the

independent variable 11. Control – is the part of an experiment that is not being tested and is used for comparison 12. Law – at the time that it is made, no exceptions have ever been found in this


Name________________________________ Date______________________

Choosing the Right Equipment Worksheet

Directions: The tools we use in science are very important. They don’t have to be complicated machines or lab equipment. Consider each hypothesis below and write the tool or tools you could use to prove each hypothesis?

1. It’s warmer on the west side of my house than on the east side.

2. Plants in the sun grow faster than plants in the shade.

3. Taking a shower is quicker than taking a bath.

4. My bedroom is longer than it is wide.

5. I weigh more in the morning than I do at night.

6. I use more milk on my cereal than my brother does.


Choosing the Right Equipment Worksheet Key

1. Thermometer

2. Ruler, calendar

3. Stopwatch or clock

4. Tape measure

5. Scale

6. Measuring cup


Name________________________________ Date______________________

Designing Experiments Directions: Discussing the Scientific Method is one thing; applying it and designing an experiment is much more intricate and requires complex thinking skills. Use the skills you have learned to analyze the following situation and answer the questions.

When cells grow uncontrollably and spread to the surrounding tissues, it is called cancer. Cancer can occur in any living organism, and if the growth of the cells continues, death can occur. Many cancers can be cured if detected and treated before the rapid spread into surrounding tissues occurs. Cancers are being studied extensively because of their impact on human beings. Many studies are done on mice because of the social and ethical implications of treating humans with cancer as lab subjects.

Suppose a scientist who has been studying cancer cells finds a chemical compound that might reduce the number of cancer cells. The scientist calls the compound Reduction, and plans a series of tests to see if the compound reduces the number of cancer cells in mice.

There were 10 mice in the small laboratory and all 10 mice have cancer. The 10 mice were divided into 2 groups of 5 each. Group A received injections of Reduction. Group B received injections of a sugar solution. The injections were given every 8 hours for 10 days.

Before beginning the injections, the number of cancer cells in a sample from each mouse was determined and recorded. After beginning the injections, the number of cancer cells in a sample from each mouse was determined and recorded every 2 days. If there was a reduction in the number of cancer cells, Reduction was working. If there was an increase in the number of cancer cells, Reduction was not working.

Table with Some of the Data Collected from Some Mice

Specimen Number of Cancer Cells

Beginning Day 2 Day 4 Day 6 Day 8 Day 10

A3 1000 1050 1050 1075 1100 1000

A5 500 600 650 725 800 825

B2 1500 1520 1530 1550 1600 1625

B3 1200 1225 1250 1260 1275 1290

1. What was the scientist’s hypothesis? 2. What was the control group? the experimental group? 3. What was the independent variable? What was the dependent variable? (be specific for

both) 4. Give all examples of what the controlled variables (constants or controls) should have been. 5. Did Reduction reduce the number of cancer cells in mice? Explain. 6. Was the scientist’s hypothesis correct? Explain. 7. What could the scientist have done to make his results more valid? 8. Should the scientist report this on the experiment and the conclusion he made? Why or why

not?


Directions: For each of the following scenarios design an experiment. List the question, hypothesis, experimental procedure, materials, technology required, independent variable, dependent variable, constants/controlled variable. Also discuss the method of data collection, technology/equipment needed, units of data to be recorded, and how often the data should be collected.

A. A veterinarian wants to determine if dogs of the same breed are healthier eating a store brand, a premium brand, or table scraps. Health is determined by weight and energy levels.

B. A forensic scientist wants to determine the best light to use for finding trace evidence on carpet. His department has always used regular flashlights, but the latest research suggests that a Forensic light source (with many wavelengths of light --including ultraviolet, white, and infrared light) is much better at finding trace evidence.


Designing Experiments Key

1. That the compound, Reduction, would decrease the number of cancer cells in mice. 2. The control group was group B that received sugar solution. The experimental group was

group A that received Reduction. 3. Independent variable: the Reduction given; Dependent variable: the number of cancer cells 4. -Between both groups everything should be exactly the same except for the chemical given

-Mice of the same age, size, sex, breed, and general health -Mice all kept in the same room, same type of cage, and same number of mice in each cage -Cages all kept in the same conditions at the same temperatures -Mice all fed the same food, and the same amount at the same time -Mice all given the same volume of injection (just the type of injection is different), same place on their body, and at the same time of day -The method of counting the number of cancer cells should be the same in both groups -The starting number of cancer cells should be almost the same

5. Students should look at the data table to answer questions. In looking at this partial data it

would appear the Reduction did not work. None of the mice had a reduction in cancer cells, and there was no difference between the tested and untested groups.

6. The scientist’s hypothesis was not correct; none of the mice showed a reduction in cancer

cells between the two groups. 7. More mice should have been used in both groups. A study is much more valid if numerous

subjects are tested. Also, more than one test should be conducted—several repeats are required, whether the results were what he wanted or not. There may have been a problem or potential source of error with the mice in these groups. Maybe Group A didn’t get enough food or had a stronger version of the cancer and that is why the medicine didn’t work. Repeat testing would hopefully catch any problems.

8. Yes, after he conducts the repeated experiments. Even if his hypothesis was incorrect, it

adds to the scientific knowledge base. Maybe another scientist was planning to test the same drug and doesn’t need to; maybe testing needs to be done with a higher dose or a different version of the drug; maybe the drug would work better in another species of animal. Every result and conclusion has significance.

A. Question: Which type of dog food is the healthiest for a dog? Hypothesis: If the premium brand is healthier for dogs, when compared to a store brand and table scraps, then dogs eating the premium brand will gain more weight and have higher energy levels Independent Variable: Type of dog food Dependent Variable: Weight gained and amount of activity Controlled Variables:

Dogs of the same breed, sex, age, and general health

An equal number of dogs in the 3 groups

Dogs fed the same amount of food, just not the same type of food


Dogs fed by the same person, in same size dish, at the same times of day, and with the same amount of water available

Dogs kept in the same environment (same yard) at the same temperature, shade, etc.

The weight of the dogs should be gathered with the same scale (units), by the same person at the same time of day

The determination of energy levels should be done with a numerical value, by the same person, at the same time(s) of day or continually throughout the day/night

Materials:

60 dogs of the same breed and approximate age, weight, and sex

3 fenced separate areas for feeding

Ample supplies of all 3 dog foods (and a measuring device for each food source)

Dishes of equal size for all dogs

A measuring cup for each food source

A metric (Kg) scale for gathering dog weight

A large yard or area for dogs to have unlimited activity; the yard should be similar in all areas with equal availability of shade, grass, etc.

A video camera and source for watching video (monitor, TV, etc)

A table and materials to record data

Experimental Procedure: 1. 60 dogs will be broken into 3 groups of 20 dogs each 2. Group A will be fed the premium brand, Group B will be fed the store brand, and Group

C will be fed table scraps 3. All groups will be fed 2 cups of food twice a day, and provided with unlimited water 4. All dogs will be weighed in kilograms every morning 5. All groups will be video-taped continuously for 4 weeks. The videos will be analyzed for

time spent sleeping/napping, time spent lying down, standing, walking, running, barking. All activity will be documented

6. All dogs, foods, environments, and methods of data collection will be monitored and controlled

B. Question: Which type light source is the best to use in finding trace evidence?

Hypothesis: If the Forensic light source is superior for finding evidence, when compared to a regular white light, then more trace evidence will be found with the Forensic Light source Independent Variable: Type of light source Dependent Variable: Number of particulates of trace evidence Controlled Variables:

Light operated by the same person, with the same methods/angles of light

Same amount, size, and color of trace evidence (hair and fibers) distributed

Same sources of trace evidence

Same type and area dimensions of carpet searched

Same search pattern used

Same method for collecting evidence

Same method for counting evidence

Materials:

4 Forensic light sources

4 regular white light sources

Batteries of the same brand for all light sources (if needed)


8 rooms of the same size/same area of carpet (10' x 10' at least)

Same carpet covering with the same color (beige) for all rooms

80 pieces of white cotton fibers

80 pieces of dark cotton fibers

80 blond hairs of about 2cm each

80 black hairs of about 2cm each

Search grid for the room sizes

2 technicians to operate light sources and collect evidence

2 evidence distributors

Coveralls (“bunny suits”) for technicians/distributers

Paper for bindle collection

Envelopes or bags for bindles

Tweezers

Trace Evidence Vacuum

4 Magnifying glasses

Experimental Procedure: 1. All light sources will be powered up or new batteries will be used 2. Evidence distributors will be assigned rooms with repeating patterns (each one will get

2 rooms for the white light source, and 2 rooms for the Forensic light source) 3. Evidence will be distributed with a particular and documented pattern in each assigned

room 4. Evidence collectors will be assigned rooms with the same method as the distributors—

so that each collector will have 2 rooms where they will use white light, and 2 rooms where they will use the Forensic Light

5. The evidence collector will work each room with the same methods of evidence location and collection, following the same grid plan

6. Evidence will be collected and marked by room and light source 7. A 2-hour interval will be allowed for each room 8. After the room has been searched, the trace vacuum will pick up any evidence left 9. Evidence will be counted and documented from each room (light source/technician) 10. Trace evidence will be catalogued according to color, size, etc. 11. Analyze the type of evidence (and color) and the number found for each light source


Expanding to Real Life

Background: There are many stories in newspapers, magazines and online about people who are using the scientific method to learn about the world and about how law enforcement is using the scientific method to solve crimes. Examples include doctors who are trying to cure diseases, environmentalists who are trying to preserve the earth’s resources, astronomers who are trying to answer questions about the universe and investigators that have solved cold cases or high profile situations. Directions: Locate an article related to science that you can use to answer the following question: How is the scientific method involved in the pursuit of knowledge or in the solving of the criminal case? Present a summary of your article to the class. Your presentation should

1. Discuss every step of the scientific method and how it corresponds to how the

investigator/scientist is making new discoveries or has solved the case.

2. Explain your own thoughts on the importance of the information and what scientific

theories/hypothesis or new technology was used.

3. Meet the minimum and do not exceed the maximum time requirements created by your

instructor.

Assessment: The Research Rubric and the Presentation Rubric will be used for assessment.


Name________________________________ Date______________________

Purchase Power

Part A: Select Your Product: (1) What product(s) will you test?

(2) (a) What do you want to find out?

(b) Write a question:

(3) (a) What do you think will happen?

(b) Write your hypothesis:

Part B: Plan Your Experiment: (4) What will you do to ensure reliable results?

(5) What safety issues do you need to address?

(6) What steps will you use in your experiment? Be specific!

MATERIALS NEEDED: Make a list of the materials you will need for your experiment and indicate the person responsible for providing the item(s). Check them off as you collect them.

ITEM PERSON CHECK WHEN BROUGHT


Part C: Collecting Data: Use the space below to create a data chart to record the information gathered during your experiment. Part D: Graphs: Use the space below, or graph paper, and the data from Part A to construct a graph that illustrates the results of your experiment. Use the space below to write a conclusion that summarizes the results of your experiment.


Name________________________________ Date______________________

Purchase Power Checklist

Objectives (0 not met, 1 met, 2 exceeded)

Part A: Decide Your Product

Identifies the product(s) to be tested 0 1 2

Question is clearly stated and addresses the topic 0 1 2

Hypothesis is clearly stated and addresses the topic 0 1 2

Materials list is complete 0 1 2

Part B: Plan Your Experiment

Provides procedures to ensure reliable results 0 1 2

Safety issues are addressed 0 1 2

Follows procedure 0 1 2

Experiment is outlined in easy-to-follow steps 0 1 2

Steps provide good detail 0 1 2

Steps incorporate methods for reliable results 0 1 2

Part C: Collecting Data

Data is displayed in an organized chart and labeled 0 1 2

Provides a sufficient amount of data 0 1 2

Graph displays results of the experiment 0 1 2

Graph is easy-to-read and labeled correctly 0 1 2

Part D: Graphs

Conclusion addresses results of the experiment 0 1 2

Conclusion addresses the hypothesis 0 1 2

Conclusion is well-written and detailed 0 1 2

Overall Points

Team members worked well together 0 1 2

Team used class time wisely 0 1 2

Team met project deadlines 0 1 2

Total Points (40 pts. possible)

Comments:


Name_______________________________________ Date_______________________________

Discussion Rubric

Objectives 4 pts. Excellent

3 pts. Good

2 pts. Needs Some Improvement

1 pt. Needs Much Improvement

N/A Pts.

Participates in group discussion

Encourages others to join the conversation

Keeps the discussion progressing to achieve goals

Shares thoughts actively while offering helpful recommendations to others

Gives credit to others for their ideas

Respects the opinions of others

Involves others by asking questions or requesting input

Expresses thoughts and ideas clearly and effectively

Total Points (32 pts.)

Comments:


Name:____________________________________ Date:_____________________________

Presentation Rubric

Comments:


3 pts. Good


1 pt. Needs Much Improvement

N/A Pts.

Topic/Content

Topic discussed completely and in-depth

Includes properly cited sources (if used)

Creativity/Neatness

Integrates a variety of multimedia effects to create a professional presentation (transition and graphics) or appropriate visual aid used

Title slide, table of contents, bibliography are included, using acceptable format

Mechanics

Grammar, spelling, punctuation, and capitalization are correct

Image and font size are legible to the entire audience

Oral Presentation

Communicates with enthusiasm and eye contact

Voice delivery and projection are dynamic and audible

Audience Interaction

Presentation holds audience’s attention and relates a clear message

Clearly and effectively communicates the content throughout the presentation



Name______________________________________ Date_______________________________________

Research Rubric


3 pts. Good


1 pt. Needs Much Improvement N/A Pts.

Question/goal Student identified and communicated a question or goal of the research

Research/Gathering information (if relevant) Student used a variety of methods and sources to gather information. Student took notes while gathering information

Conclusion/Summary Student drew insightful conclusions and observations from the information gathered. Information is organized in a logical manner

Communication Student communicated the information gathered and summary or conclusions persuasively. Student demonstrated skill in the use of media used to communicate the results of research

Reflection Student reflected on the importance of the research and its potential application


Comments:

Documents

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