Worksheet created by T. Trimpe 2003 http://sciencespot.net/
Scientific Method Name __________________________
Controls and Variables – Part 1
SpongeBob and his Bikini Bottom pals have been busy doing a little research. 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.
Which people are in the control group?
What is the independent variable?
What is the dependent variable?
What should Mr. Krabs’ conclusion be?
Why do you think 8 people in group B reported feeling better?
2 – Slimotosis
Sponge Bob notices that his pal Gary is suffering from slimotosis, which occurs when the shell
develops a nasty slime and gives off a horrible odor. His friend Patrick tells him that rubbing seaweed
on the shell is the perfect cure, while Sandy says that drinking Dr. Kelp will be a better cure. Sponge
Bob decides to test this cure by rubbing Gary with seaweed for 1 week and having him drink Dr. Kelp.
After a week of treatment, the slime is gone and Gary’s shell smells better.
What was the initial observation?
What is the independent variable?
What is the dependent variable?
What should Sponge Bob’s conclusion be?
