This summer, all over Scotland, thousands of pupils will sit the new National Examinations for the first time but, even among supporters of the new curriculum, there are persistent concerns that the new system will leave many pupils sitting fewer exams than they did under the old Standard Grades.

These concerns were first raised by parents last year when it appeared many schools were submitting pupils for a lower average of National examinations compared to the average number of Standard Grades. It has emerged that the average has fallen from 7.3 to 6.8; in addition, the total number of entries for the exams is down 10%, with languages faring particularly badly.

Such a fall in the number of exams being taken, although small, was always a risk because of the structure of the new curriculum. In the old days, pupils would make their subject choices at the end of second year, leaving them two years to study for Standard Grade exams. Under the new Curriculum for Excellence (CfE), however, that choice is delayed by a year to the end of third year, leaving only one year to complete the course.

The new figures on the National exams suggest that some schools are finding it difficult to make such a timetable work and that the only solution is for pupils to take fewer exams. This was always one of the anxieties the Scottish Parent Teacher Council had about CfE; the organisation was also concerned that the longer-term consequence would be a limiting of access to qualifications.

The Scottish Qualifications Authority has sought to reassure parents on this issue by drawing attention to the central idea of CfE: that the education system should not be merely a machine that churns out pupils capable of passing exams and that it should encourage a broad education likely to set them up for life after school.

That idea is still sound in principle and there is also still time for the drop in the exam average to correct itself in later years.

Some able pupils, for example, may be skipping their National exams and going straight on to Highers. Pupils studying six exams instead of seven may also be able to study the subjects in greater depth, fulfilling one of the tenets of CfE.

But, even if the new curriculum does, in years to come, stabilise itself in this way and even if we accept that CfE is on its way to broadening education, the importance of exams should not be under-estimated. They are a key staging post in any pupils' academic life and an important way of measuring progress and achievement.

In this context, the drop in average from 7.3 to 6.8 should serve as a warning sign along the way, particularly if the new system is backing pupils into a corner and forcing them to drop important subjects such as languages or sciences.

Many influential voices in education have also been saying consistently that, while eight subjects is too many, six is too few, and these voices should not be ignored.

The new National qualification is the most significant shake-up in our exam system for a generation but it must be able to achieve its aims of broadening and reforming the learning experience without significantly reducing the number of qualifications with which pupils emerge at the end of the process