Revising for maths exams is unlike revision in other subjects - you need to do some maths. So, you need to consider not only how well a revision guide provides information but also how it shows students the right way to tackle questions. The three GCSE books by Paul Metcalf pass these tests fairly well. The presentation of facts is clear and colour is sensibly used to emphasise key points.

Total Revision is the most comprehensive in its approach, with plenty of short questions for quick checking of recall. The answers contain many “tutorial” notes on particular points. There are also sections of longer worked exam questions with full examiner’s notes on the good and bad points in the candidate’s answer, as well as examination questions for the stdent to try.

Instant Revision is small enough to slip into a pocket and as a result contains only short questions, but it could be just the thing to use in those spare minutes waiting for the bus. The Do Brilliantly GCSE book concentrates on improving exam technique, starting each section with worked exam questions, and showing how to gain full marks.

There is much less emphasis than in the other two books on the key facts. I am not sure about the wisdom of including a “don’t make these mistakes” section - it is usually best to reinforce the positive and leave out the negative in case students absorb the wrong message!

Do Brilliantly at AS Maths is rather disappointing when compared with the GCSE book. It reverses the approach, starting each section with a recap of key facts before moving on to worked exam questions. It is also only in black and white - do the authors assume that more mature students don’t need visual reinforcement?

Ian Wilson is head of Rydens School, Walton-on-Thames, Surrey