ACARA v9 CONTENT DESCRIPTION “compare findings with those of others, consider if investigations were fair, identify questions for further investigation and draw conclusions”
Builds on planning and running a fair test. Now the test is finished, so the next job is to make sense of the results: compare them with what another group found, check that both tests were fair, draw a conclusion, and think of a new question to try next.
Compare your findings with another group
When you finish a test, it helps to compare your results with a classmate or another group. If you both get a similar answer, you can trust the finding more. If your answers are very different, that is a clue. It might mean one test was not fair, or that something was measured in a different way. Comparing is not about who is right; it is about making the answer stronger.
My results next to another group's
Both groups timed how many seconds an ice cube took to melt on five surfaces. Switch between the table, bars and line to compare the two sets of findings.
My group's melt times. Another group tested the same five surfaces and got 30, 60, 47, 73 and 41 seconds. The two sets rise and fall in the same order, so the groups agree: metal melted ice fastest and cloth the slowest. Findings that match across groups can be trusted more.
Was each test fair?
Before you trust a comparison, check that both tests were fair. A fair test changes only one thing and keeps everything else the same. If your group used big ice cubes and the other group used tiny ones, the melting times cannot be compared fairly. When findings disagree, an unfair step is often the reason, so it is the first thing to look for.
Find the reading that does not match
Five groups each timed the same ice cube melting on the same metal tray. Four groups got close times, but one is far off. Click the reading that does not match the others.
Click the point that does not fit the pattern of the others.
Draw a conclusion from the data
A conclusion is a short statement of what your results show about the question. It must come from the data, not from what you hoped would happen. The question was which surface melts ice fastest. Both groups found metal was quickest and cloth was slowest, so the conclusion is that ice melts faster on metal than on soft surfaces. Sort which statements the data really supports, and which do not belong in a conclusion.
Which statements does the data support?
The conclusion should be drawn only from the melt-time results both groups collected. Decide which statements the data actually supports.
Claim: Ice melts faster on metal than on soft surfaces like cloth.
On metal the ice melted in about 31 seconds, faster than on every other surface.
On cloth the ice took about 72 seconds, the slowest of all the surfaces.
Both groups agreed that metal was quickest and cloth was slowest.
The metal tray was a nice shiny silver colour.
We did the test on a Friday afternoon.
Decide whether each statement is evidence for the claim, or not.
Ask a new question for next time
Good science does not stop at one answer. A finished test usually points to a new question you could investigate next. Now that you know metal melts ice fastest, you might wonder whether the ice would melt even quicker on a sunny windowsill, or whether a thicker metal tray works better. A new question keeps the investigating going and is the start of the next fair test.
Why this matters
Comparing your findings with others, checking that tests were fair, drawing a conclusion from the data, and asking a new question are the steps that turn a single experiment into real science. Scientists, doctors and engineers all compare their results with other people's before they trust an answer.
Quick self-check
1. Your group and another group both timed how fast ice melts. Why is it useful to compare your findings?
2. Your group says warm water melts ice fastest, but another group got the opposite. The best next step is to...
3. A conclusion is...
4. After finishing a test, a good new question for further investigation would be:
5. One of your readings is very different from all the others and from the other group. What does it tell you?