1. DO NOW! 1. Identify three things that are accomplished during
the initial steps of the science process.
2. What is a claim? Give an example.
3. What is a fact? Give an example.
DO NOW!

2. Investigating Claims Pre-Lab Activity
You hear many claims made every day.
Advertisers make claims about the usefulness or effectiveness of their products. Your friend may claim to be able to do something that you do not think he or she can really do.
Do you believe all claims that people make?
Have you ever bought a product based on a claim made in an advertisement, only to find that the product did not work as you expected it to?

3. When does a claim become a fact?
 Scientists look for evidence to support or refute a claim. Evidence can help you determine which claims are facts and which are opinions or even misrepresentations.
 For example, if one of your classmates claims to be the fastest runner in the class, you could gather evidence by holding a series of races.
 If your classmates claim is true, that person should win all of the races. If another individual wins the races, your classmate’s claim was simply an opinion not supported by evidence.

4. READ the conflicting claims below.
 Student A claims that a person will be able to squeeze a clothespin more times in a minute if the person exercises first. Student A suggests that exercising produces a faster pulse rate, which indicates that the blood is getting to the muscles faster.
 Student B claims that a person will be able to squeeze the clothespin more times in a minute if the person does not exercise first. Student B suggests that exercise takes energy away from the muscles, and a person who has been resting will have more energy.

5. Which of the two students do you agree with?
How could you find out for sure
which claim is correct?
Design an Experiment
You must now design and conduct a controlled experiment to gather evidence that will determine which of the two claims is correct.
Refer to the scientific method to help you design your controlled experiment.
Be sure your experimental methods will provide enough data to form a valid conclusion.
You will have to conduct several trials.

6. Please record the following information in your lab notebook:
The Effect of Exercise on the Rate of Clothespin Squeezing
Problem: How does exercise affect the rate of clothespin squeezing?
Hypothesis: _____________________________________
_____________________________________
Materials: _____________________________________
Procedure:

7. Make two groups. Each group should have the same number of participants with equal numbers of boys and girls. The first group will be the control (rest). The second group will be the experimental group (exercise).
The control group will rest for two minutes. The experimental group will exercise for two minutes. Exercise includes running-in-place, jumping jacks, and push ups.
Provide participants in both groups with a clothespin. Each participant must count the maximum number of times they can squeeze the clothespin in one minute. Repeat for two more trials.
Record the data in the data table.
Calculate an average for each group and record in data table.

8. Hold a spring-type clothespin between your thumb and index finger.
DO NOW!
Gathering Data
Hold a spring-type clothespin between
your thumb and index finger.
Pinch the ends together completely
(until the two ends touch) and release them.
Do this as rapidly as possible for one minute while counting the number of times you squeeze the clothespin. Record this number : _____

9. CONTROL GROUP
(rest)
# of times
clothespin squeezed
EXPERIMENTAL
GROUP
(exercise) T1 T2 T3
AVG
100
180 99 50
159
129
141
158
122
185
160
130
102
190 80
143 96
120
169
140
155
145
156 56
173
204
170
197
240
152
189
139
103 73
110
105
224 70
150 93
230
131
116
OVERALL AVERAGE:

10. CONTROL GROUP EXPERIMENTAL
# of times
clothespin squeezed
EXPERIMENTAL
AVERAGE:

11. DO NOW! 1. Take out the rough draft of your lab report and data table.
2. Calculate the average for both the control and
experimental group.
DO NOW!

12. How to Write a Conclusion for Science Lab Reports
1. Restate your hypothesis.
2. Does the data support your hypothesis? EXPLAIN…
3. Provide an explanation for the results.
4. Provide suggestions for improvement:
 What were some things that went wrong?
 How can the experiment be improved?
5. Provide two suggestions for further research.