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GCSE results: Sitting exams early could 'limit potential'

22 August 2013 Last updated at 11:59 BST

There has been a drop in the proportion of GCSE exam entries awarded top grades, for the second year in a row, with head teachers saying changes have caused "a lot of turbulence" in grades.

But Andrew Hall, from the Assessment and Qualifications Alliance, says an increase in the number of pupils sitting the exams early is "limiting in some way" the students' potential.