1. Smithers conducted an experiment to test if a special juice increased worker productivity. He assigned one group the juice and one group no juice. However, the group without juice was more productive, so the juice did not increase productivity. 2. Homer tested if coconut juice removed green slime in his shower by spraying half with coconut juice and half with water. After 3 days, there was no change in slime on either side, so coconut juice did not reduce slime. 3. Bart tested if microwaving mice made them stronger by microwaving one group and not the other, then having them push blocks. Both groups pushed blocks equally, so microwaving did not increase strength.

1. Identify the Controls and Variables
Smithers thinks that a special juice will increase the Identify the:
productivity of workers. He creates two groups of 50
workers each and assigns each group the same task 1. Control Group: Group B
(in this case, they're supposed to staple a set of
papers). Group A is given the special juice to drink 2. Independent Variable: Special Juice
while they work. Group B is not given the special
juice. After an hour, Smithers counts how many
stacks of papers each group has made. Group A made 1,587 stacks, Group B 3. Dependent Variable: Productivity of workers
made 2,113 stacks.
4. What should Smithers' conclusion be?: The
special juice did not increase workers
productivity
5. How could this experiment be improved?
Retest it!
Homer notices that his shower is covered in a strange 6. What was the initial observation?: Green
green slime. His friend Barney tells him that coconut slime in the shower
juice will get rid of the green slime. Homer decides
to check this this out by spraying half of the shower Identify the-
with coconut juice. He sprays the other half of the 7. Control Group: Side he sprayed with water
shower with water. After 3 days of "treatment" there
is no change in the appearance of the green slime on 8. Independent Variable: Coconut Juice
either side of the shower.
9. Dependent Variable appearance of green
slime
10. What should Homer's conclusion
be? Coconut juice did not reduce the amount of
slime in the shower
Bart believes that mice exposed to microwaves will become extra strong Identify the-
(maybe he's been reading too much Radioactive Man). 11. Control Group Mice that had not been
He decides to perform this experiment by placing 10 exposed
mice in a microwave for 10 seconds. He compared these
10 mice to another 10 mice that had not been exposed. 12. Independent Variable: microwave
His test consisted of a heavy block of wood that blocked
the mouse food. he found that 8 out of 10 of the 13. Dependent Variable: Strength of the mice
microwaved mice were able to push the block away. 7
out of 10 of the non-microwaved mice were able to do
the same. 14. What should Bart's conclusion be?:
Microwaving did not cause the mouse to be
stronger than non microwave mice
15. How could Bart's experiment be improved?
Retest it
Krusty was told that a certain itching powder was the Identify the-
newest best thing on the market, it even claims to cause 16. Control Group Group A
50% longer lasting itches. Interested in this product, he
buys the itching powder and compares it to his usual 17. Independent Variable: Experimental Itching
product. One test subject (A) is sprinkled with the original Powder
itching powder, and another test subject (B) was sprinkled
with the Experimental itching powder. Subject A reported 18. Dependent Variable: Itchiness time
having itches for 30 minutes. Subject B reported to have
itches for 45 minutes.
19. Explain whether the data supports the

2. advertisements claims about its product. The
time was reduced by 1/3 so the claim is not
supported
Lisa is working on a science project. Her task is to answer the question: "Does 20. Describe how Lisa would perform this
Rogooti (which is a commercial hair product) affect the speed of hair growth". experiment. Identify the control group, and the
Her family is willing to volunteer for the experiment. independent and dependent variables in your
description.
Find a group of people willing to be tested.
Have 2 (control group) of them use a “fake”
hair care product and 2 of them use Rogooti
(independent variable). Measure hair growth
(responding variable) over 4 weeks for each
subject.