Exam boards should change their marking so that bright A-level science students are not penalised, private and state school heads said yesterday.
In a joint statement issued at the Head Masters' Conference in Dublin they said pupils were deterred from taking science in the sixth form because they believed that it was harder to get good grades than in art subjects.
The heads accused the exam boards of "norm referencing" - allocating a very similar percentage of candidates to each grade each year. Since a higher proportion of bright pupils take science rather than arts, they suffer accordingly.
Research has shown those with an average of grade B at GCSE gain on average half a grade less in A-level physics, maths and chemistry than would have been expected from their GCSE results.
Graham Able, head of Hampton School, a London private school, said it should not be beyond the wit of the exam boards to set papers in all subjects every year to the same standard, so that it was as easy, or difficult, to get a grade A in physics as in English or media studies.
John Dunford, president of the Secondary Heads Association, said: "There is no such thing as an A-level standard, gold or otherwise."
Heads said they did not want the exams made easier but the boundaries between grades should be changed so it was easier to get As and Bs in science.
George Turnbull, of the Associated Examining Board, said the boards did not use norm referencing. "There are no external constraints on the numbers getting grades. The standard in each subject is the one set when A-level began and maintained by the boards ever since. A decision to change that standard could not be taken by us."
Heads said they would like all pupils to continue some science in the sixth form. The statement says: "As a nation we need a scientifically literate population as well as a ready supply of appropriately qualified scientists."Reuse content