Underachievement at A or AS-Level — even by potentially very able students — is extremely common. Every year in August, the narrators of the story change, but the tale itself remains remarkably consistent: “My GCSEs were good, but the AS was a disaster”, combined with: “I had no idea I was struggling — I thought I was doing well”, or the opposite: “I found it very difficult — I felt like giving up”.

The difference between GCSE and A-Level is huge. This can either catch students by surprise, causing demoralisation, or they do not fully realise (it can actually be quite difficult for a student to judge how he or she is doing) and simply drift.

They then never quite get on top of the subject, and receive unexpectedly mediocre grades. If nothing changes the following year, they can go on to finish with poorer A-Levels than they should. Regardless of the cause, the result is anguish for students and parents alike.

What can be done? New A-Level specifications were introduced in 2008 for most subjects, and this month sees the first results. Significant changes in content in many cases, the abolition of coursework for sciences, new ways of assessing practical skills, and the introduction of the A* grade, all add up to a more substantial shake-up of A-Levels than we have seen for a while. This presents a challenge not just to students, but to teachers and tutors too, and complicates matters.

If your final A-Level grades are poor, one possibility is to retake. This will involve a commitment of time and effort on your part, and it will involve deferring university entry for a year. But you will potentially be able to improve your grades and increase your options.

Retaking must be taken seriously or it will be a waste of time. You will have to consider some important questions. Why were the grades so disappointing? Which subjects will you retake? The whole exam or selected units?

What will be done differently to ensure success this time round? January exams or June? Note that many modules are unavailable in January.

Preferably, you should discuss the issues with somebody who has relevant knowledge and experience. This is now all the more important, because of the new specifications.

If you use the services of a specialist tutorial centre, such as Oxford Science and Maths Tutors, you will receive appropriate advice in these areas. Our own retake classes involve students being taught mostly individually, or in small groups of two or three. The tutors are experienced, and skilled in explaining their subjects to others.

Our emphasis is on thorough learning of material, regular exam practice, the development of efficient study and revision methods, and exam technique. If you are studying for your retakes by yourself, or at a local school, we can help by providing additional tutoring support and guidance.

If it is your AS exams, in which the results have been poor, then you are in a much better position; the damage can be repaired without you having to take a year out.

We have a great deal of experience with students in this situation, and are able to guide them through that critical final year.

Typically, this would involve them coming to weekly small group evening classes after school. We teach the AS material up to Christmas, and they usually retake some or all AS units in January.

We then go on to cover the A2 topics for the summer exams. But the exact plan varies from student to student. Alternatively, you could opt to change school and to do your final year with us.

Whatever your situation, if you have not done as well as you thought, it is not the end of the world. There are steps you can take to move forward.

Zaid Marham, principal, Oxford Science and Maths Tutors. E-mail: info@get-those-grades.com