In our strange national obsession with examinations, quantity seems almost as important as quality. What we have in this country is a system of rote marking, in which exam papers are processed in industrial quantities by overstretched and underpaid staff. As inexorably as grades have inflated, standards of marking have slipped.

In our strange national obsession with examinations, quantity seems almost as important as quality. What we have in this country is a system of rote marking, in which exam papers are processed in industrial quantities by overstretched and underpaid staff. As inexorably as grades have inflated, standards of marking have slipped.

This is the true significance of the news that some private schools are pulling out of the independent school league tables. Ostensibly, this is an attack on the idea of league tables – which certainly have problems, in both the state and private sectors. Not least of which is to add to the obsession with exam results. But the idea of giving parents more information cannot, and should not, be uninvented.

What is more important is that elite schools, including Eton, are losing confidence in the integrity of public exam marking. This demands a radical overhaul, not just of the exam boards (which have an incentive to make their papers easier to attract more customers), but of the whole exam system. The suggestion that an "A grade with distinction" should be added at A-level is beside the point, and the private schools are right to reject that too. The A* grade has not solved the problems of GCSEs, and a similar tinkering would not help at A-level. The fundamental problem is that we have too many public exams and pupils are under ever-greater pressure to take too many at once.

If Estelle Morris, the Secretary of State for Education, were really bold, she would scrap GCSEs, let schools assess who would benefit from post-16 academic studies, and build on the certificate of achievement, recording basic skills in literacy and numeracy. Then she would try to reverse grade inflation at A-level by reconstituting the exam boards so that they do not have a financial interest in lower standards. And she would encourage schools to use the Continental five-subject baccalaureate as an alternative to A-levels.

Not only would that be a more educationally sound system, if she cut the voting age to 14, she would also win the grateful votes of the school population and keep Labour in office forever.