GCSE English: Low grades shock for Wales in January exams
6 March 2014 Last updated at 19:50 GMT
Head teachers from across Wales have raised concerns over the "unexpectedly low" results for GCSE English language exams sat earlier this year.
One teaching union said it had received a "flood of concern" after the results for the January exams in Wales were "far below what was expected".
In 2012, a row over GCSE English exam results led to thousands of papers being re-graded.
The Welsh government said comparisons with previous exams were "misleading".
BBC Wales education correspondent Arwyn Jones reports.