Secondary schools are now allocating an average of pound;50,000 just for entering students for A-level, GCSE and vocational assessments, a 31 per cent increase in just two years, the survey of 110 schools and colleges shows.

If these figures were extrapolated across the country the total bill for exam entries would exceed pound;250 million.

When the pound;30m costs of national curriculum tests are added, the total testing bill nears pound;300m.

John Dunford, general secretary of the Secondary Heads Association, said:

“This is damning evidence of the excessive system of external assessment in this country. Schools have never received additional money for fees, and there’s never been any recognition of the steep increase in costs caused by Curriculum 2000 and frequent increases in charges from the boards.”

The figures, which are for last year’s exams, were compiled as around a million students sit A-levels and GCSEs. They do not include the costs of exams officers and extra administrative staff or postage bills which now often run into hundreds of pounds.

And heads are facing a new cost. From September next year, under the Government’s workforce agreement, schools will have to employ invigilators, rather than teachers, to administer exams.

Many schools are already taking on staff, at an extra cost of around pound;6,000 for a typical secondary, despite receiving no specific Government funding.

Combined costs for schools and colleges were 13 per cent higher in 2003 than in 2002. Last year was the first full year of exams under the Curriculum 2000 reforms which led to a surge of entries. The rise for colleges was smaller than for schools.

Early indications are that costs for this year will climb further.

England’s three boards all raised their charges well above inflation this year. At the largest, AQA, fees rose by 14 per cent for A-level, and 11 per cent for GCSEs.

Ministers have pledged to reduce the assessment burden in schools in the long run through the Tomlinson inquiry, which is proposing a new qualifications system by 2014.

But today, Mike Cresswell, AQA’s director general warns that costs will rise again if proposals from the exams regulator, Ken Boston, for GCSEs to become fully modular by 2010, bear fruit.

In an interview with The TES, Mr Cresswell said that the move would lead to students taking more exam papers, in both Years 10 and 11. Boards would pass on increased costs to schools.

The re-sit culture at A-level is being blamed in part for the soaring costs, though some students have to pay for their own re-takes.

The growing popularity of the more expensive vocational exams is also a factor. The most expensive qualification, a 12-unit vocational A-level from the OCR board, now costs pound;172.80.

Many students have been facing timetable clashes at A-level and AS.

Aylesford comprehensive in Warwick said up to a tenth of its sixth-formers had been in this position this year, one facing a day of exams from 8.30am to 6pm.

Headteachers are increasingly frustrated. One said: “Exam costs are now out of control.” Another said: “Price increases have been more than inflation, but we have no choice but to pay.”

A Qualifications and Curriculum Authority spokeswoman said that the pound;100m the Government was investing in the exams system to 2006 would ease the burden on schools, partly by reducing the need for boards to raise their prices.

A Department for Education and Skills spokeswoman said it was up to the QCA to comment.

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