Review

This variable is the one thing that changed on purpose...

• Dependent Variable

• Control

• Independent Variable

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

• how tasty the breakfast is

You are testing how the amount you water a plant affects its growth. What would be the INDEPENDENT VARIABLE in this experiment.

• They type of pot you put the plants in.

• The amount you water each plant.

• The amount of sunlight the plants get.

• The amount the plant grows.

An experiment is performed on plants to see how different liquids affect plant growth. Each plant in the experiment is given a different liquid; water, apple juice, or milk. Each plant has the same amount of soil, sunlight, and listens to the same music. In this investigation, the independent variable is ...

• The type of plant
• The amount of sunlight
• The type of music
• The type of liquid

Sadie is testing how the age of a seed affects how fast plants grow. Look at the picture to see if you can figure out what makes her experiment unfair. Mark all that apply.

• She used different types of seeds/plants.

• The plants are in different pots.

• She did not plant very many plants.

• Seed age might not make a difference.

Anything that may affect the results of an experiment 

• variables
• quantitative data
• hypothesis
• steps

A possible explanation to a problem that has not yet been tested. 

• data
• theory
• hypothesis
• fact

This variable in an experiment is the one being deliberately changed by the scientist.  It is the only variable that is different between groups.

• dependent variable
• independent variable
• data
• control group

What is the best written dependent variable for this hypothesis:

 "If I add salt to the plant, then it will grow taller."

• grow taller
• plant growth

• amount of salt
• add salt

A student is planning an experiment to find out how the height from which he drops a ball affects how high the ball bounces. The dependent variable is the _____.

• Diameter of the ball
• Force acting on the ball
• Height that the ball bounces
• Height from which the ball is dropped