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Teenagers scored record GCSE results yesterday with the biggest rise in top grades for nearly 20 years. But the results also show a sharp fall in GCSE entries, suggesting that schools are concentrating more on the quality than the quantity.

More than one in five exam papers was awarded an A* or A this year and the proportion achieving at least a grade C soared to two thirds. The overall pass rate at all grades rose slightly this year to 98.4 per cent. Despite record rises in results, the number of GCSE exams taken by all students fell by 158,242, or nearly three per cent.

This can partly be explained by a 6,000 fall in the number of 16-year-olds between 2007 and 2008, but exam board chiefs suggested that other factors were at work.

The growing tendency for schools to enter their brightest students for maths and, to a lesser extent, English GCSEs early in the academic year, in November, accounts for about 10,000 of the drop in maths entries.

This frees students to concentrate more on their remaining GCSEs in the summer. In the case of maths, it gives students more time to devote to maths-related subjects, such as additional maths and statistics in the summer. It will also enable the brightest students to start studying for the AS-level maths early, according to Greg Watson, chief executive of the OCR exam board.

The drop in entries is also explained by the growing numbers of independent schools that are opting out of GCSEs in favour of the International GCSE exam (I-GCSE), which they regard as more stretching than the standard exam. At City of London boys’ school in London, the head teacher, David Levin, decided in September 2006 to take English language, English literature, maths, physics, chemistry and biology I-GCSEs.

No other school takes as many and this year the school achieved its best results, with nearly half its entries (49 per cent) coming in at A*. “The I-GCSE is better because there is no coursework involved. That’s particularly important for us as a boys’ school because boys hate coursework. This frees us to teach the boys the core subjects for longer,” Mr Levin said.

Jerry Jarvis, managing director of the Edexcel exam board, said that there was also plenty of evidence that state schools were dropping GCSEs for some pupils in favour of vocational qualifications.

Mike Cresswell, director-general of the AQA board, said that the number of GCSEs taken by each student had also been in steady decline from just over eight in 2003 to just over seven.

John Dunford, general secretary of the Association of School and College Leaders, said that schools appeared to be concentrating more on quality, not quantity of results. “They recognise that it’s of no benefit to a pupil to do 10, 11 or 12 GCSEs. It’s better to have eight or nine good grades,” he said.

The results also showed a continued decline in the number of teenagers studying foreign languages, the result of a government decision in 2004 that languages should no longer be compulsory after age 14. The number of French GCSE entries was down by 6.8 per cent on last year while German dropped by 5.4 per cent. The number of pupils taking Spanish rose.

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