Sometimes at the end of a practical lesson pupils do not have complete or expected observations.

Try using videos and photographs of results to summarise the practical. For example, in chemistry, halogen displacement test tube reactions are conducted.

Pupils will not always make the expected subtle observations. I have a video clip to show the experiment and photographs in a PowerPoint slide to summarise the results.

Once the practical is complete, pupils can watch the video, look at the slide and check that they have recorded the correct observations.

They can then study their results to enable them to recognise and explain the pattern using their scientific knowledge, followed by the writing of ionic equations To view video and photographic resources of chemistry experiments go to www.chemistry-videos.org.uk, produced as part of my Gatsby Teacher Fellowship.Emma Baker is a head of chemistry and advanced skills teacher at The Downs School in Compton, Newbury