1. Identify the Controls and the Variables Simpson’s Practice Worksheet Key

2. Worker Productivity 1. Control Group = Group B 2. Independent Variable = Special juice 3. Dependent Variable = # of papers stapled 4. Smithers’ conclusion? Juice does NOT increase productivity 5. How could this experiment be improved? Various answers permitted

3. Slimy Shower 6. Initial observation = The shower is slimy 7. Control Group = The half sprayed with water 8. Independent Variable = Coconut Juice

4. Slimy Shower 9. Dependent variable = Appearance of slime 10. Homer’s conclusion = Coconut juice does NOT get rid of slime

5. Mouse Strength 11. Control Group = 10 Mice not exposed 12. Independent Variable = Microwave exposure 13. Dependent Variable = Strength 14. Bart’s conclusion? Microwaved mice MIGHT be stronger 15. How could this experiment be improved? Repeat it, use mice that are all the same age, gender, etc

6. Itching Powder 16. Control Group = Subject A 17. Independent Variable = Exposure to itch powder 18. Dependent Variable = Length/time of itching 19. Does the data support the advertisement claims? Yes – Subject B did report prolonged itching