Year 4 Science: Conclusions and evaluation
Part of the Year 4 Science working scientifically revisited chapter. Chapter overview · whole chapter on one page
Conclusions and evaluation
A conclusion answers the question that the test asked. It must be based on the results, not on a guess. A good report says what was done, what was found, and what the conclusion is.
To evaluate a test, ask: was it fair? Did the results match the prediction? Could a result be wrong? How could the test be made better? This is how scientists check their work.
Key ideas
- A conclusion answers the question the test asked, and is based on the results.
- Find differences by comparing two results.
- Three trials are more reliable than one trial.
- To evaluate, ask whether the test was fair and how it could be improved.
Method. Subtract the smaller average from the larger one.
- Read the averages. Towel B averages 16 ml, and Towel A averages 10 ml.16 and 10
- Subtract. 16 minus 10 is 6, so Towel B soaks up 6 ml more.16 - 10 = 6
- Write the answer. 6
Check. Check: 10 plus 6 makes 16. ✓
Watch out. Subtract the smaller number from the larger number.
Method. Look at the averages.
- Find the largest average. The largest average is 16 ml, which is Towel B.16 ml
- Write the conclusion. So the conclusion is that Towel B soaks up the most water.Towel B
- Write the answer. Towel B
Check. The bar for Towel B is the tallest on the chart. ✓
Method. Think about what one trial can show.
- Think about one trial. One trial can give a result that is unusual, by chance.unusual
- Think about three trials. Three trials show whether a result is typical, and their average is more reliable.typical
- Write the answer. Accept any reason that says three trials show whether a result is typical, and that the average is more reliable.
Check. Three trials make a better test than one trial. ✓
Watch out
Watch out: a conclusion must match the results. Do not write that a towel is the best if the test did not measure what makes a towel good.
Try it at home or school (with a grown-up). Repeat the paper towel test from section 1.2 with two towels of your own, with a grown-up. Keep the same water and the same time, and do three trials. Find the average for each towel, and write one conclusion from your results. Say one thing that could make your test better.
Exam tip
Grown-up tip. Ask: “What did your results show? How sure are you? What would you change next time?” Let your child write the conclusion in one sentence, using the words from the results.
Exercise 1E Conclusions and evaluation
Method. Subtract the smaller average from the larger one.
- Read the averages. Towel B is 16 ml, and Towel A is 10 ml.16 and 10
- Subtract. 16 minus 10 is 6.16 - 10 = 6
- Write the answer. 6
Check. Check: 10 plus 6 is 16. ✓
Method. Find the smallest average.
- Look at the averages. The averages are 10, 16 and 13 ml.10 ml is the smallest
- Read the name. The smallest average, 10 ml, is for Towel A.Towel A
- Write the answer. Towel A
Check. Towel A has the shortest bar on the chart. ✓
Method. Compare the two averages.
- Read the averages. Towel C is 13 ml, and Towel B is 16 ml.13 and 16
- Compare them. 13 is smaller than 16, so Towel C soaks up less.less
- Write the answer. less
Check. Thirteen is less than sixteen. ✓
Method. Look at the averages.
- Find the largest average. The largest average is 16 ml.16 ml
- Write the name. The towel with 16 ml is Towel B.Towel B
- Write the answer. Towel B
Check. A conclusion answers the question the test asked. ✓
Method. Add the three trials, then divide by three.
- Add them. 9 plus 11 plus 10 makes 30.9 + 11 + 10 = 30
- Divide by three. 30 divided by 3 is 10.30 divided by 3 is 10
- Write the answer. 10
Check. Check: 10 + 10 + 10 = 30. ✓
Method. A conclusion says what the results show.
- Look at a). Towel B soaked up the most water, which is what the results show.results show
- Look at b). Testing next week is a plan, not a conclusion from results.a plan
- Write the answer. a
Check. A conclusion is based on the results of the test. ✓
Method. Look at the three trials for Towel B.
- Read the trials. The three trials for Towel B are 16, 15 and 17 ml.16, 15, 17
- Find the biggest. The biggest of these is 17 ml.17
- Write the answer. 17
Check. The average of the three is 16 ml, so 17 is above it. ✓
Method. Read the key idea in section 1.5.
- Read the key idea. A conclusion answers the question the test asked.question
- Write the answer. question
Check. The question is the starting point of the test. ✓
Method. Think about how many trials are needed.
- Think about one trial. One trial can be unusual, so one result is not enough to be sure.not enough
- Decide. Mo should repeat the test to check the result, so the answer is no.no
- Write the answer. no
Check. Three trials and an average are more reliable. ✓
Method. Think about how much evidence there is.
- Think about the test. Three trials on one day is a small amount of evidence.small amount
- Write the reason. The result might not be typical, so “always” claims too much.too much
- Write the answer. Accept any reason that says the test used only three trials, so the result might not be typical.
Check. A conclusion should not claim more than the evidence shows. ✓
Method. Think about what would make the results more trustworthy.
- Think about the test. More trials, or the same method each time, make the results more reliable.more reliable
- Write one way. Choose one change and write it as a sentence.one change
- Write the answer. Accept any way, such as repeating more trials, or using the same method and the same water each time.
Check. Evaluating a test helps us improve it. ✓
Method. Think about what a conclusion is.
- Think about the results. The results are the evidence that the conclusion uses.evidence
- Write the reason. A conclusion that does not match the results is not supported by evidence.supported
- Write the answer. Accept any sentence that says the conclusion should be based on the results, so that the evidence supports it.
Check. Good scientists check that their conclusion follows from the evidence. ✓