Pupils are to be given a question-by-question breakdown of their GCSE and A-level results over the next fortnight, which could give parents the ammunition to sue schools for poor teaching.

Edexcel, one of the country’s largest exam boards, will give heads feedback on the performance of all their students and teachers when they publish their results for the examinations, starting on Thursday. Not only will heads and teachers be able to compare results for questions across year groups, but some fear that parents and pupils will be able to do the same.

Teaching unions have expressed concerns that Edexcel’s latest move could be exploited by parents to punish underperforming staff and have called for the information to be used solely for in-school improvements. Next week more than 200,000 sixth-formers will receive their A-level results amid expectations that a quarter of entries could achieve an A-grade, thereby putting greater pressure on students aiming for places at the top universities.

Jerry Jarvis, the managing director of Edexcel, admitted that revealing more information could encourage parents to sue schools, but he said that it was crucial that pupils knew whether they had been taught badly. “The last thing we want to do is damage the teaching environment, when we’re short of heads and so on,” he said. “So we don’t want this technology to be used to sue schools, but we know that parents want the best for their children, so the pressure to get the results is going to come.”

Last year the examination board piloted the results feedback system of 1,500 pupils at 10 schools. From next week the results of all the 1.2 million pupils taking Edexcel GCSE and A-level examinations will be made available to heads all over Britain. Teachers will also be able to apply to see the results of their pupils. They will be able to compare them across the year group, with the national average and with past years. But they will not be able to look at other schools’ results.

The students will also be able to access their own results, module scores and grades online. But they will have to ask their teachers for the school’s comparative figures. They will also be able to tell how close they were to a higher grade and gauge whether they should ask for a re-mark. Mr Jarvis is also considering arming students with their test results throughout the year, as well as their classmates’ average, the national average in a subject or course and that of neighbouring schools. “If I then see that I’m likely to gain a C and I can see that the class is performing at a much lower level than others, what do I do with that information?” he asks.

Steve Sinnott, the general secretary of the National Union of Teachers, said that part of the problem was that parents were not expert at understanding the marking system.

Martin Ward, deputy general secretary of the Association of School and College Lecturers, said most heads would welcome the information, and that they would be concerned only if it allowed parents to make comparisons between classes. “I don’t think it will be easy to make comparisons on that basis, but obviously there’s a concern that parents will try to and come to erroneous conclusions,” he said.

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