The Education Secretary has announced changes to reduce the number of pupils in Wales taking their GCSE exams early.
It comes after concerns were raised in the summer when Kirsty Williams said the current system is 'unsustainable' and was putting 'unnecessary pressure' on pupils, teachers and school budgets.
An independent review by Qualifications Wales found concerns about the growing use of early and multiple entry which posed 'risks to students' which are 'not easily justified'.
In response, the Education Secretary said from summer 2019, only a pupil's first entry to a GCSE examination will count in their school's performance measures.
The current policy allows schools to count the best grade from multiple sittings.
Almost a fifth of entries for GCSE English Language, Welsh Language and Maths taking in the summer were from pupils in Year 10.
It is estimated more than £3.3million is spent on early entry.
Qualifications Wales said it is a matter which 'divides opinion'.