LightMySky

Fair testing (age 9+)

Use test results to make predictions and set up further comparative and fair tests to investigate new questions

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What a learner can do afterwards

  • Use results from an investigation to make a specific, testable prediction
  • Design a follow-up test to verify the prediction
  • Explain the reasoning linking the original results to the new prediction

The lesson

You already know how to run a fair test and read what the results tell you. The next step is using the pattern in your results to make a real guess about a new situation, then testing that guess.

50 mL4100 mL10150 mL7
Ben watered three identical plants different amounts. The 100 mL plant grew the tallest.
Try it together

Ben's results show a pattern: too little water or too much water both slowed growth, but 100 mL worked best. Ben predicts that a fourth plant given 125 mL will grow taller than the 50 mL plant but shorter than the 100 mL plant, somewhere around 8 or 9 cm.

Good to know

A strong prediction names a number or a clear outcome you can check. Saying 'something will happen' is not a prediction you can test.

Good to know

To check the prediction, run a new fair test: keep everything the same except the one thing you're testing. Then compare the new result to your prediction to see if your reasoning was right.

Use the pattern in your results to make a specific prediction, then run a new fair test to check it.

Watch it

Where it sits

Where this leads

Jobs that lean on this skill. Follow one to see everything it is built on.

Then practise

8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.

Fair testing (age 9+) · Science, ages 9 to 11 · LightMySky