One of Britain’s biggest examination boards was last night accused of “battery farming” pupils to get them through their GCSEs.

The charge came as Jerry Jarvis, managing director of Edexcel, announced a new commercial service for schools that could involve teenagers sitting scores of online practice tests in the build-up to their GCSEs.

The first 20,000 pupils in 400 schools will take part in trials of the new science and maths tests before sitting their GCSEs this summer.

Initially they will cover foundation maths, higher maths and science GCSEs. Eight more subjects will be added from 2009. Mr Jarvis said that the new scheme, called ResultsPlus Progress, was designed to help to assess pupils’ grasp of concepts behind their GCSEs so they know where they need to improve for their final exams.

“We will provide all the tools and techniques and analysis to teachers in the classroom that we can to improve attainment.

“Half of kids still don’t get five good GCSEs. That’s our target. We think that target can be broken very, very easily,” he said.

But experts feared that the new service, which costs schools £20 per pupil, would add to the enormous burden of testing, which already dominates children’s education. They also questioned whether “improving attainment” was a proper role for an exam board.

Alan Smithers, Professor of Education at the University of Buckinghamshire, said: “They are turning schools into battery farms.

“Mr Jarvis is taking on himself a conflict of interest. His job is to impartially assess attainment of pupils. It’s not his responsibility to raise attainment.”

John Dunford, the general secretary of the Association of School and College Leaders, agreed.

“It’s the job of exam boards to measure attainment, not to raise it. Exam boards need to be above suspicion in the way they deal with school candidates,” he said.

Dylan William, deputy director of the Institute of Education in London, said that while it was acceptable for exam authorities to produce teaching material, it was not acceptable for them to “give hints” to students on how to improve their exam performance. “It’s very hard to see how this isn’t insider trading,” he said.

Others dismissed the online tests as a crude marketing tool for Edexcel. With schools in England spending £400 million a year in fees to exam boards, competition between the main exam boards for business is intense.

Mr Jarvis defended the scheme, but accepted that it was likely to lead to more allegations of schools drilling pupils and teaching to the test.

“The more we concentrate as an organisation on improving attainment, the more we are going to be accused of supporting the notion that we teach to the test,” he said.

He added that the tests would help schools that were under tremendous pressure to boost attainment.

“You have to be realistic about the pressure that teachers are under. League tables drive careers and the success of students in tests is extremely important to schools.”

A spokesman for the Department for Children, Families and Schools said: “Schools are free to use or not to use such commercial products, as they see fit. This is one of many that Edexcel and other organisations produce and market.”

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