Based on the student’s experimental design, what is their dependent variable? 

• The height from which the sphere is dropped
• The angle at which the sphere impacts the ground
• The type of material the sphere is made of
• The diameter of the crater

Which of the following is a variable that the students should have kept constant?

• The drop height of the sphere
• The thickness of the sand in the tray
• The diameter of the crater
• All of the above

In order to replicate the student’s experiment, what additional information would you need? 

• The different heights to drop the sphere from
• The mass and volume of the plastic sphere
• The type of sand to use: fine, coarse, or rocky
• All of the above

Upon evaluating their procedure, which is MOST true?

• The students provided precise numbers to use in setting up their variables
• The students conducted multiple trials, which will help them judge whether the experiment and results are reliable
• The students only changed and tested one variable in their experiment
• The experiment could easily be repeated by other students who would get the same results 

Based on the student’s experimental design, what is their independent variable? 

• The amount of soapy water
• The substance added to the soapy water
• The height of the soap suds
• Filtering the water

Which of the following variables is a constant(s)?

• Filtering the water
• The amount of substance added to the water
• The amount of soapy water used
• All of the above

Which was the control of the experiment?

• 50 mL of soapy water
• The cup that had no substance added
• 10 grams of sugar, salt, and Epsom salt
• The experiment could easily be repeated by other students who would get the same results 

Upon evaluating their procedure, which is MOST true?

• The students provided precise numbers to use in setting up their variables, which will allow the experiment to repeated by others  
• The students conducted multiple trials, which will help them judge whether the experiment and results are reliable
• The students failed to use any constants; therefore, the experimental results are not valid.  
• The students did not use enough soapy water to get accurate results