Hundreds of thousands of pupils in England are stuck in a cycle of resits, as they try to achieve a grade C in maths and English.
Schools and colleges say it is putting pressure on their teachers, and their budgets.
In 2013, the government introduced a policy that said students in England who fail to get a grade C or above in GCSE maths or English should carry on studying the subject, or subjects, until the age of 18, with the aim of achieving this mark.
James Longman reports.
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