There are still those who seem unable to grasp why there appears to be a discrepancy between the ever-increasing exam successes of our children and their ever-diminishing abilities to perform against their peers elsewhere in the world (“World rankings and rising results don’t add up, says exam boss”, 18 May).

It’s to do with commercial reality and competition. On the one hand, there are schools, which compete for pupils, because pupils mean money. Schools gain more pupils by being successful, measured by exam results. On the other hand, there are exam boards, which compete for exam entries, because exam entries mean money. Exam boards gain more exam entries through the success of their examinees, again measured by exam results. Factor in, also, that schools and exam boards have an input into the marking of the papers, and perhaps a light will begin to dawn. It’s not hard to see where the mutual self-interest lies.

Jon Belk, MFL teacher, Lincolnshire.