Track quiz
Here are the six rules, in the exact words each bench uses.
| Part | The rule, as the bench applies it |
|---|---|
| A guess you can test | A hypothesis is a claim a test could show to be wrong. It is often a guess about why, or about what will happen. It names something you can observe or measure. A claim nothing could go against is not a hypothesis. |
| Change one, keep the rest the same | Change one thing and keep the rest the same. Then the changed thing is the one cause you are testing. Change two things and you cannot tell which caused it. Change nothing and nothing is tested. |
| Something to compare with | A result on its own has nothing to compare with. So run a second group that is left alone. Compare the two groups. Treat them alike, except for the one thing you test. |
| Write it down as you go | Write down what you see as you work, not afterwards. A conclusion may use only what is on the sheet. What you did not write down cannot be claimed later. |
| Supports, goes against, or says nothing | A record that fits a claim supports it. A record that contradicts it goes against it. One clear record against a claim weakens it. A record that does not touch the claim says nothing. |
| Plan it before you start | Plan the test before you start. Name the claim. Change one thing and keep the rest the same. Keep a comparison group. Write down what you see as you go. |
Which claim could a test show to be wrong?
"A puri puffs, or it does not." Why is this not a hypothesis?
Test A uses thin dough in hot oil. Test B uses thick dough in cooler oil. B is slower. What is wrong?
You test whether the kind of flour matters. What do you keep the same?
Twenty seeds are soaked. Seventeen sprout. What do you need before you can say whether soaking helps?
Two groups are treated exactly alike. They give 14 and 16. What does this show?
Wednesday was counted but never written down. What can the conclusion use?
The claim is "Hot oil puffs a puri faster." The record says hot oil took 14 s. Cooler oil took 9 s. What does it do?
Chapter 1 is Exploring the Investigative World of Science. Read it now. You have planned tests, kept records and judged evidence.
Next comes a chapter about the invisible. It is The Invisible Living World: Beyond Our Naked Eye.