The overhaul of the GCSE grading system will make it easier to spot the brightest students, Ofqual suggested.
Currently, in some subjects such as maths and science, high numbers of pupils achieve A* and A grades which makes it difficult to pick out the top students.
Chief regulator Glenys Stacey said that in these cases "you then begin to question whether the qualification is doing its job in differentiating sufficiently your most able students."
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