Variables and Fair Tests (Grade 7)
Free printable Grade 7 science inquiry worksheet on variables. Students read three investigations and name the independent, dependent and controlled variables, then write a hypothesis.
Variables and Fair Tests
Read the three investigations, then name the variables in each. The independent variable is the one thing changed on purpose, the dependent variable is what is measured, and controlled variables are kept the same.
Investigation A. Mia times how long one sugar cube takes to dissolve completely in 100 mL of water. She repeats it with the water at 20, 40, 60 and 80 degrees Celsius, stirring at the same rate each time.
Investigation B. Noah drops the same toy car from the top of a ramp and measures how far it rolls after the ramp. He tries ramp heights of 10, 20, 30 and 40 cm on the same floor, releasing the car without pushing it each time.
Investigation C. Ava plants bean seeds in identical pots of the same soil and gives each pot a different amount of fertiliser: 0, 2, 4 and 6 grams. All pots get the same water, light and temperature. After three weeks she measures the height of each seedling.
- 1.Investigation A: what is the independent variable?
- 2.Investigation A: what is the dependent variable?
- 3.Investigation A: name one variable that must be controlled (kept the same).
- 4.Investigation B: what is the independent variable?
- 5.Investigation B: what is the dependent variable?
- 6.Investigation B: name one variable that must be controlled (kept the same).
- 7.Investigation C: what is the independent variable?
- 8.Investigation C: what is the dependent variable?
- 9.Investigation C: name one variable that must be controlled (kept the same).
- 10.Investigation A: write a hypothesis. Use the form "if ... then ... because ...".
- 11.What is a hypothesis?
- 12.What is the dependent variable in an investigation?