Plan a fair experiment

Grade 6 Science Worksheet

Circle the best answer.

1. 1.

   What is changed, wing size; what is measured, flight distance; groups, A: indoors, B: outdoors, windy. Bo tests whether wing size changes how far a paper airplane flies. Plane A flies indoors; plane B flies outside on a windy day. What makes this unfair?

   • The distance was measured in meters, not in steps
   • Nothing; the test is already fair
   • The planes flew in different places and wind
   • The planes were made of paper
2. 2.

   What is changed, towel brand; groups, A: 5 s, B: 30 s. In Esme's towel test, towel A is dipped in water for 5 seconds and towel B for 30 seconds. What should be fixed?

   • Add two more brands to the test
   • Dip each towel for the same time
   • Dip both for 30 s, but in different amounts of water
   • Nothing; the dipping time does not matter

3. Read this first

   Use this

   A book-stack ramp with three different balls beside it. Investigation card: what is changed, ramp height; what is measured, distance rolled; problem, different ball each time.

4. 3.

   Jun rolls a ball down ramps of different heights and measures how far it rolls, using a different ball each time. What should change?

   • Use one ramp height for every trial
   • Use a brand-new ball for every trial
   • Change the floor too, for more variety
   • Use the same ball for every ramp height

5. Flights (model data)

   Trial 1	Trial 2	Trial 3	Average
   5.2 m	4.8 m	5.0 m	?

6. 4.

   Kira's paper airplane flew 5.2 m, 4.8 m and 5.0 m in three trials. What is the average distance?

   • 4.8 m
   • 5.2 m, the longest flight
   • 15.0 m
   • 5.0 m
7. 5.

   Table, Trials, with columns Trial 1, Trial 2, Trial 3, Average. Why does Luz run three trials instead of one?

   • Three trials make the hypothesis come true
   • More trials give the scientist more things to change
   • One trial is enough if it is done carefully
   • One trial could be off; an average is more reliable
8. 6.

   Groups, light: 1 plant, dark: 1 plant. Milo's plan tests one bean plant in light and one in a dark cupboard. What would make the results more reliable?

   • Use several plants in each group
   • Skip the plant in the dark cupboard
   • Add a third plant in different soil
   • Use one plant, but measure it twice
9. 7.

   Four question cards about sugar and water. Which question names both variables, by Pia's check?

   • Is sugar good or bad?
   • Does water temperature change how fast sugar dissolves?
   • What is sugar made of?
   • Does sugar dissolve at some point?
10. 8.

    Note: average of 3 trials. Salted ice cubes melted in 12 minutes on average; plain cubes took 25 minutes. Which conclusion fits Tala's data?

    • Salt makes everything melt faster
    • In this test, salt made the ice melt faster
    • Salt made the ice cubes melt more slowly in this test
    • Salt will melt ice on any road in winter
11. 9.

    Note: average of 3 trials. Which conclusion fits Zee's paper-towel results?

    • Towel C soaked up the most water of the three towels
    • Towel B will be the strongest and cheapest too
    • Towels A and B soaked up the same amount
    • Towel B soaked up the most water in this test
12. 10.

    Note: 5 plants per group, after 2 weeks. Ari's hypothesis: if a plant gets more light, it will grow taller. Do the data support it?

    • Yes, and light is the one thing plants need
    • No; the plants kept in the dark cupboard grew taller
    • Yes; the plants in light grew taller in this test
    • There is no way to tell without a control group