The national curriculum emphasises the importance of enquiry-based learning in primary science. This means that pupils will have valuable chances to explore and investigate, but it also necessarily means that they will spend a considerable amount of time writing about their enquiries and recording their findings.

It’s important, therefore, that they have a secure understanding of the language associated with investigative work - and this can be trickier to provide than you might think.

Some terminology misconceptions may be easily addressed with individual pupils through clear, constructive feedback. However, others may need to be explicitly taught. Here are some simple suggestions for teaching three important terms. A word of caution, though: I would definitely not teach all three in one lesson as these are terms that pupils often confuse. Detailed explanations about what they mean can be found on the Association for Science Education (ASE) website.

1. Fairness 

Teachers may lack confidence in their own understanding of what a fair test is and when it is needed. Put simply, if all but one of the variables are controlled, then the test is fair. However, problems may occur when writing about whether a test was fair if pupils have only come across the word in the context of behaviour; they might assume that the test was fair if all members of their group have been allocated an equal role in the investigation.

In language lessons we would always draw attention to dual meanings or uses of words, so why should science lessons be any different? In my opinion, fairness is best taught explicitly at the planning stage when discussing variables. Start by choosing a test that you know is fair and spend time talking about what makes it so. More able learners may then be able to consider the extent to which an investigation is fair. 

2. Reliability 

Pupils may be in the habit of carrying out a science investigation three times and then finding the average, which could be mistaken for them having an understanding of reliability. This should not be assumed, as pupils may simply be used to carrying out this process, without understanding the reasons behind it. 

You need to make pupils explicitly aware that they are repeating the process to increase the  reliability of their results. Before asking them to find the average, allow time for them to look at their results. During this time, ask them to consider whether their repeated results are similar and whether they can see a pattern. Are there any obvious anomalies? By looking at results in this way it should be clearer to pupils what reliability is and why it is important. 

3. Accuracy 

Pupils who are keen to add extra details to their write-ups may comment on whether their results are accurate. Address this concept when pupils are selecting the units of measurement or the measuring equipment they will use for their investigation. For example, ask them why using a ruler with millimetres will allow them to obtain results closer to the true value when measuring small distances than if they used a metre stick.

In the same way, urge them to consider why using a stopwatch rather than trying to count seconds on a clock is more likely to yield accurate results. You can then ask more able pupils to reflect on whether they could make changes to the way they carried out an enquiry to improve the accuracy of their results. 

Marianne Evans is a Year 5 and 6 teacher in North Wales