You’ve probably heard a few scare stories about data. Yet, used well - and only when needed - data can be among a teacher’s most powerful tools.

Tales of data-related woe arose amid the chaos that surrounded the removal of levels (which had been in place for 26 years) in 2014. Since then, we have seen a shift - welcomed by many teachers - away from collecting data for the purposes of accountability (“What do we need for Ofsted?”) towards using data to support teaching and learning (“What has been taught and how well have pupils understood it?”).

So, in light of this change in approach, it’s important to differentiate between the types of data you are likely to be confronted with and then consider how best to make use of them in the classroom.

Mix of assessment

Most schools will use a mix of teacher assessment and tests, some of which will be useful, others less so. Teacher assessment may simply take the form of an overall summative judgement, such as “emerging”, which is of very little value. One key reason for the removal of levels was that they were broad, best-fit indicators that told us almost nothing about what pupils could and couldn’t do. Some new approaches are no different and should not be relied upon.

Of far more use is tracking against key objectives in which individual learning maps are created that show gaps in, and depth of, learning. This will provide valuable detail that can inform your teaching. Regular testing will also provide useful information on what pupils do and don’t know.

Question-level analysis highlights gaps, areas for support and opportunities to stretch children further. Plotting pupils’ test scores over time reveals dips and provides a useful progress measure, while plotting test scores in one subject against another identifies pupils with inconsistent results. Test scores can also be plotted against teacher assessments in order to spot discrepancies.

Identify specific groups

Ideally, test scores should be captured in your tracking systems so they can help to inform teacher assessment and be included in key reports to show performance of pupil groups. A word of warning, though: while tests are undeniably useful, they only represent a pupil’s attainment on one particular day and may not reflect their overall ability.

It is vital that key contextual information is available to teachers so that they can easily identify specific groups of students, such as disadvantaged pupils and those with SEND, and track their knowledge gaps and progress. Awareness of prior attainment is also essential as it gives an indication of future attainment.

Information can be a powerful tool when used correctly but it is easily skewed if used for multiple purposes. A focus on accountability or performance management can distort data and render it unreliable. And there is a balance to be struck between what is useful and what adds to your workload. Spending your life ticking boxes is counterproductive.

Remember the mantra: do what has the most impact. Your time is best spent teaching.

James Pembroke founded Sig+, an independent school data consultancy, after 10 years working with the Learning and Skills Council and local authorities