Experimental Design

How many variables should you change in an experiment?

• none
• 1
• 2 or more
• depends on the type of experiment

Does the size of deer effect the size of its heart?

What is the independent variable?

• Size of Deer

• Gender of Deer

• Size of its heart

• Age of deer, gender, and height

The variable that depends on changes to the independent variable. 

• control group
• dependent variable
• experimental variable
• independent variable

Students used various temperatures of water to see which one dissolved candy faster. 
What was the Independent Variable?

• Amount of Candy
• Amount of Water
• Temperature of Water
• Time for Candy to Dissolve

Diego wants to know how drinking milk affects how tall Dora grows. Which is the independent variable?

• Drinking milk.

• Diego's growth.

• Dora's growth.

• Chocolate or plain milk.

Students wanted to see if the type of material affected the temperature after being placed under a heat lamp for 10 minutes.

What is the dependent variable for this investigation?

• Type of material (rocks, sand etc)

• Temperature after 10 minutes

• Time under the lamp

• Heat lamp, amount of material

Dory set up an experiment to see how the mass of a ball affects the distance it rolls off a ramp. What is the dependent variable?

• distance traveled by the ball
• height of the ramp
• mass of the ball
• ball type

What is the part of the experiment that contains the independent variable?

• control group
• experimental group
• hypothesis
• dependent variable

The part of the experiment that does not contain the independent variable. Used for comparison.

• Control Group
• Experimental Group
• Results
• Data

What is the DEPENDENT variable (effect) in this experiment?

"Does eating breakfast improve test scores?"

• eating breakfast or not

• the grade you got on the test

• what time you get up in the morning

• what you eat for breakfast