Identifying Variables

What is the DEPENDENT variable (effect) is this experiment?
"Does eating breakfast improve test score?" 

• eating breakfast or not
• the grade you got on the test
• what time you get up in the morning
• how tasty the breakfast is

What is the INDEPENDENT  variable (cause) is this experiment? 
"Which type of medium is best for plant growth?" 

• height of plant (cm)
• type of medium (soil vs. sand)
• amount of medium
• types of plant

What is the DEPENDENT variable (effect) in this experiment?
"Do tall people jump further than short people?"

• height of the person
• weight of the person
• how fast the person runs
• how far the person jumps

What is the INDEPENDENT variable (cause)in this experiment?
"Which type of metal, copper or aluminum, conducts heat faster?" 

• size of metal
• types of metal
• time it takes to heat up
• shape of the metal

Bonnie wants to test whether adding Bio-fertilizer 'x' will help plant grow. What is the "controlled group" in this experiment?

• plant sprayed with Bio-fertilizer 'x'
• plant without the Bio-fertilizer 'x'

Which variable is NOT a constant in this experiment?
"Is Bounty paper towel more absorbent than sparkle paper towel?

• the size of paper towel
• the amount of water for the paper towel to absorb
• amount of water the paper towel absorbed
• the shape of paper towel

What is the INDEPENDENT variable (cause) in this experiment?
"Will fish school more if a predator is present?" 

• whether there is a predator or not
• number of fish school together
• type of predator
• type of fish

Which variable is NOT a constant in this experiment?
"What type of medium do earthworms prefer?"

• type of medium
• amount of medium
• direction of the earthworm
• types of earthworm

A test company wants to see whether having a special study program such as SAT prep will help increase test score. What is the "experimental group" in this experiment?

• the usual study program
• special study program

Janet wants to see whether drinking coffee will improve productivity. What is the INDEPENDENT variable in this experiment (cause)?

• increase productivity
• Having coffee or not
• the brand of coffee
• the time drinking the coffee