Working scientifically: asking questions and comparing fairly

A question science can answer

“Which ball bounces highest?” can be tested. “Which ball is nicest?” cannot. A scientific question must have an answer you could measure or see, and two people doing the test must get the same answer.

Changing only one thing

If you want to know which ball bounces highest, you must drop every ball from the same height onto the same floor. Change the ball; keep everything else the same. That is what makes a comparison fair, and it is the single idea Checkpoint tests most often in this strand.

Looking carefully and recording

Write down what you see as you see it, not afterwards from memory. A simple table with a row for each try is enough at this stage, and it makes the pattern much easier to spot.