Experimental Design REVIEW
Read the description for each experiment and answer the questions.
1 - Patty Power
Mr. Krabbs wants to make Bikini Bottoms a nicer place to live. He has created a new sauce
that he thinks will reduce the production of body gas associated with eating crabby patties
from the Krusty Krab. He recruits 100 customers with a history of gas problems. He has 50 of
them (Group A) eat crabby patties with the new sauce. The other 50 (Group B) eat crabby
patties with sauce that looks just like new sauce but is really just mixture of mayonnaise and
food coloring. Both groups were told that they were getting the sauce that would reduce gas
production. Two hours after eating the crabby patties, 30 customers in group A reported
having fewer gas problems and 8 customers in group B reported having fewer gas problems.
Identify Mr. Krabbs’:
1. Problem (Question he is trying to answer): Customers who eat Crabby Patties end up
with gas problems.
2. Hypothesis (His testable answer to the question): The new sauce he has created
will reduce the production of body gas associated with eating crabby patties.
3. Materials (Items he will use in his experiment): 100 customers, crabby patties, new
sauce, mayonnaise and food coloring sauce.
4. Independent Variable/Manipulated Variable (The condition that Mr. Krabbs is
purposely changing): The type of sauce.
5. Dependent Variable/Responding Variable (The condition that is affected BY the
independent variable): The number of gas problems reported.
6. Controlled Variables (The conditions in the experiment that remain the same for
every group): The number of volunteers in each group, the number of crabby
patties each volunteer eats, the amount of time after eating the patties in which
the data is recorded.
7. Experimental Group (The test subjects exposed to the new conditions): Group A, the
group that is eating crabby patties with NEW sauce.
8. Control Group (The test subjects exposed to the original/normal conditions): Group
B, the group that is eating the mayonnaise and food coloring sauce.
9. Procedure (Steps he will take to test his hypothesis): He has 50 of them (Group A)
eat crabby patties with the new sauce. The other 50 (Group B) eat crabby patties
with sauce that looks just like new sauce but is really just mixture of mayonnaise
and food coloring. He then records the data.
10. Observations (His data; His results after testing his hypothesis): 30 customers in
group A reported having fewer gas problems and 8 customers in group B reported
having fewer gas problems.
11. Conclusion (What Mr. Krabbs can INFER based on his observations): The new sauce he
has created does reduce the production of body gas associated with eating crabby
patties.
3 – Marshmallow Muscles
Larry was told that a certain muscle cream was the newest best thing on the market and
claims to double a person’s muscle power when used as part of a muscle-building workout.
Interested in this product, he buys the special muscle cream and recruits Patrick and
SpongeBob to help him with an experiment. Larry develops a special marshmallow weightlifting program for Patrick and SpongeBob. He meets with them once every day for a period
of 2 weeks and keeps track of their results. Before each session Patrick’s arms and back are
lathered in the muscle cream, while Sponge Bob’s arms and back are lathered with the
regular lotion.
Which person is in the control group? Spongebob.
What is the independent variable? The type of cream.
What is the dependent variable? Muscle power.
What should Larry’s conclusion be? Larry needs to find 98 more friends to
include in his experiment.
4 – Microwave Miracle
Patrick believes that fish that eat food exposed to microwaves will become smarter and
would be able to swim through a maze faster. He decides to perform an experiment by
placing fish food in a microwave for 20 seconds. He has the fish swim through a maze and
records the time it takes for each one to make it to the end. He feeds the special food to 10
fish and gives regular food to 10 others. After 1 week, he has the fish swim through the
maze again and records the times for each.
What was Patrick’s hypothesis? Fish that eat food exposed to microwaves
will become smarter and will be able to swim through a maze faster.
Which fish are in the control group? Fish that eat regular food.
What is the independent variable? Exposure to microwaves.
What is the dependent variable? Time to get through the maze.
Look at the results in the charts. What should Patrick’s conclusion be? Fish that eat
microwaved food will not become smarter.
Time
Initial Amount
After Week 1
After Week 2
Patrick
18
24
33
Sponge Bob
5
9
17
The Bikini Bottom gang loves science class and wanted to do a little research. Read the
description for each experiment and use your knowledge of the scientific method to
answer the questions.
(1) Flower Power
SpongeBob loves to garden and wants to grow lots of pink flowers for his pal Sandy. He
bought a special Flower Power fertilizer to see if will help plants produce more flowers. He
plants two plants of the same size in separate containers with the same amount of potting
soil. He places one plant in a sunny window and waters it every day with fertilized water.
He places the other plant on a shelf in a closet and waters it with plain water every other
day.
What did SpongeBob do wrong in this experiment? Explain. He has
THREE independent variables. He placed one plant in sunlight and the
other in the dark. He gave one plant fertilized water and the other
plant regular water. He waters one plant every day and waters the
other plant every OTHER day.
What should SpongeBob do to test the effectiveness of Flower Power
fertilizer? Write an experiment.
He plants 100 plants of the same size in separate containers with
the same amount of potting soil. He places 50 plants in a sunny
window and waters them every day with fertilized water. He places
the other plants in a sunny window and waters them with plain
water everyday. He should then record the number of flowers each
plant produces.
(2) Super Snails
Gary is not the smartest snail in Bikini Bottom and believes he can improve
his brain-power by eating Super Snail Snacks. In order to test this hypothesis,
he recruits SpongeBob and several snail friends to help him with the
experiment. The snails ate one snack with each meal every day for three
weeks. SpongeBob created a test and gave it to the snails before they
started eating the snacks as well as after three weeks.
Based on the data provided, do the Super Snail Snacks work?
Explain your answer.
There is not enough significant data to support Gary’s
hypothesis. Even though Gary did get smarter, his friends did
not get similar results. Larry did not get smarter. Barry only
got smarter by 2% and Terry actually got dumber. In
addition, Gary needs to test his hypothesis on at least 100
snails in order to make his experiment valid.
Spongebob Worksheet created by T. Trimpe 2003 http://sciencespot.net/
Smithers thinks that a special juice will increase the productivity of workers. He
creates two groups of 50 workers each and assigns each group the same task (in this
case, they're supposed to staple a set of papers). Group A is given the special juice to
drink 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 made 2,113 stacks.
Identify the:
1. Control Group: Group B
2. Independent Variable: The amount of special juice
3. Dependent Variable: How many papers are stapled
4. What should Smithers' conclusion be? Drinking the special juice does not improve the productivity of
the workers.
5. How could this experiment be improved? Count the results after a longer period of time.
Homer notices that his shower is covered in a strange green slime. His friend Barney tells
him that coconut juice will get rid of the green slime. Homer decides to check this this out
by spraying half of the shower with coconut juice. He sprays the other half of the shower
with water. After 3 days of "treatment" there is no change in the appearance of the green
slime on either side of the shower.
6. What was the initial observation?
Identify the-
7. Control Group: The half of the shower that is NOT sprayed with coconut juice.
8. Independent Variable: The amount of coconut juice sprayed.
9. Dependent Variable: The amount of green slime
10. What should Homer's conclusion be? Coconut juice does not get rid of green slime in showers.
Bart believes that mice exposed to microwaves will become extra strong (maybe
he's been reading too much Radioactive Man). He decides to perform this experiment by
placing 10 mice in a microwave for 10 seconds. He compared these 10 mice to another
10 mice that had not been exposed. His test consisted of a heavy block of wood that
blocked the mouse food. he found that 8 out of 10 of the microwaved mice were able to
push the block away. 7 out of 10 of the non-microwaved mice were able to do the same.
Identify the-
11. Control Group: The 10 mice NOT exposed to microwaves.
12. Independent Variable: Microwave time
13. Dependent Variable: strength
14. What should Bart's conclusion be? There is no significant difference between the two groups. His
results do not support his hypothesis. Therefore, he can conclude that exposing mice to microwaves will
not make them extra strong.
15. How could Bart's experiment be improved? Using 100 mice.
Simpson’s experiments from http://www.biologycorner.com/worksheets/controls.html