Figures for this year show a modest increase in Higher grade passes and a larger jump in passes at credit level in Standard grade.

But with the trend seemingly ever upwards, it has prompted questions of whether standards are slipping, or whether Scotland's schoolchildren really are getting smarter.

Pass rates in England and Wales have also risen, but while a debate has raged there about whether standards have fallen, this has not been reflected to the same extent in Scotland.

Exam techniques are improving

At least part of the reason is the rate of change. While A level pass rates have risen sharply over a relatively short period, in Scotland the increase has been more gradual.

Less than three years ago - partly in response to the English debate - the Scottish Office Education Department published an independent study of Higher standards.

The Scottish Council for Research in Education looked at three key Higher exams: English, maths and biology, between 1987 and 1994.

The final report concluded that standards had been maintained and in some cases candidates were showing increased performance levels.

Newspaper columnists

So why the rise in pass rates? The good news for parents - and bad news for newspaper columnists - appears to be that young Scots are getting better at passing their exams.

Among the probable factors are better learning methods and greater emphasis on exam techniques.

Others think pupils are simply working harder, knowing that good Higher grades are more important than ever before in an increasingly competitive market for good jobs and university places.