The number of students who had GCSE and A-level grades changed after appeal has soared by nearly 20 per cent in a year, according to Ofqual.
Figures released this morning by the exams watchdog reveal a 48 per cent increase in exam scripts being returned for re-marking this year compared with 2013.
In total, 304,500 GCSE papers were returned by schools to be re-marked, up 56 per cent on last year, and 145,150 A-level scripts were sent back, up by 34 per cent.
Challenges by schools led to a 19.1 per cent increase in grades being changed this year, and headteachers said the figures showed there was a growing lack of confidence in the exam system.
“We’re not surprised to hear that there has been a significant increase in requests for re-marks,” said Brian Lightman, general secretary of the Association of School and College Leaders.
“Many schools have told us of a worrying number of results simply did not reflect how well students should have done. In an informal poll we carried out of 200 schools, 95 per cent said they had submitted appeals and 25 per cent had seen changes to their students’ marks.
“There is a growing lack of confidence in the exam system, which has been exacerbated by frequent and ad hoc changes to qualifications. These are confusing to teachers, students, parents and employers.”
Mr Lightman said schools were no longer able to trust the marks being given to students.
The watchdog said there had been a 19 per cent increase in the number of exam scripts marked this summer due to government changes that meant students had to take all of their exams in the summer term.
Education minister Nick Gibb said: "It is essential that students can be confident that their hard work will be accurately assessed and the exams they sit properly marked.
"While the figures released today show the proportion of grades changed remains relatively low, every such change has a big impact on the individuals affected.
"Parents, pupils and schools must have faith in exam marking and we are working closely with Ofqual and the exam boards to ensure this is the case."
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