ScienceYear 9

Working scientifically: variables, evidence and conclusions

Learn Working scientifically: variables, evidence and conclusions for Year 9 pupils (ages 13–14). Free practice questions, lessons and worked examples — aligned to the UK National Curriculum.

What you'll learn

  1. 1

    A fair test changes ONE thing and keeps everything else the same.

  2. 2

    Testing whether light affects plant growth: change the light (independent), measure the height (dependent), keep water, soil, pot size and temperature identical (control).

  3. 3

    In that experiment, what is the dependent variable?

  4. 4

    Repeating readings does not remove a systematic error. If the balance reads 2 g heavy every time, ten repeats give you the same wrong answer more precisely.

  5. 5

    What do repeat readings actually reduce?

  6. 6

    Apply it: a correlation is not a cause. Ice cream sales and drowning both rise together — because hot weather causes both. A third factor explains the link.

  7. 7

    Two things rise together. What can you conclude?

Practise Working scientifically: variables, evidence and conclusions with Whizlo

Free AI-tutored lessons, unlimited practice questions, and progress tracking for ages 13–14. Aligned to the UK National Curriculum.