Last week, another batch of AS-level and A2 exams began. But, apart from the usual pressures associated with last-minute revision, hapless sixth-formers have had to cope with a brand-new problem. Re-marked results from the last set of papers they sat in January are still causing chaos and confusion.

A few years ago, appeals against exam results were rare. Now, with more exams and more candidates, and with main exam periods in January as well as June, inevitably there are more re-marks. Indeed, appealing against AS and A2 results seems one of the biggest growth industries in education.

So much is at stake, not least precious places at university. The most recent re-marks of the January papers - or results enquiries, as exam boards quaintly call them - hit schools only last week.

Our school learned of its latest in a long line of grade changes a few days before the current exams started. Since the January results were first released back in March, no fewer than 10 individual grades have gone up.

This may seem an insignificant number, but is around 5 per cent of the total. Small figures like these can make a massive difference to a school’s standing in the dreaded league tables - and, of course, to an individual’s entire career.

Some re-mark decisions make little sense, even to teachers. With wild swings and spectacular gains, the atmosphere resembles a swingometer on election night.

In two English literature cases last week, our January “results” went up by two whole grades (from Cs to As). That’s the difference between an “average” and an “excellent” candidate. The reaction of one disbelieving (currently) C-grade sixth-former was typical: “Who marks these papers? How could they get it so wrong?” Such wild discrepancies and grade swings fatally undermine confidence in the fledgling system - and have a knock-on effect throughout entire school year-groups.

“Will my grade go up on the re-mark?” was the question on many sixth-formers’ lips; what they should have been worrying about was the next set of papers.

Parents must be scratching their heads in disbelief. So, too, must universities. What are they to make of the candidate applying to them with three Cs in mid-winter who, a couple of months and a few appeals later, turns out to have straight As?

Students, too, must suddenly re-assess career and university options, as they discover they have done dramatically better than expected. Take the case of the laid-back teenager I teach who, having cruised along comfortably as a C-grade candidate all year, now has to adjust to increased expectations, after his OCR-board poetry and drama result was hiked up to an A. Have we reached the stage where separate league tables of school exam results are needed: both before and after the year-round appeals procedure has been exhausted?

As one experienced school exam officer puts it: “The position is only going to get worse. With the new ‘modular’ system now applying in all subjects, there are so many more exams - and each candidate can see how heshe has done in a particular paper. In the past, only the overall A-level grade could be questioned. Now exam boards are bigger - and more can go wrong, particularly in January, when the deadlines for examiners are very tight.”

With each appeal for an AS-level or A2 re-mark costing pound;20-pound;25 per candidate, there is a real danger that the new system will favour only those schools with the time and resources to pursue the costly process of appealing.

The whole system seems a mess. We need a return to one-off, final exams. This would take away the pressure point that so much new exam marking in January has created, and end the current climate where uncertainty, multiple appeals and re-marks seem to have become the norm.

A more traditional, “terminal” exam system would not in itself solve the growing problem of mismarking. But it would place more onus on examiners to get the mark right first time. It would also give exam boards the precious extra time to make sure an additional layer of checks is in place, helping to restore faith in the flagging system.

At present, with so many appeals flying around, there is very little confidence that AS or A2 marking makes sense.

Dr Andrew Cunningham teaches English at Cranleigh school, Surrey, and is a former GCSE examiner