A headteachers’ union is to write to the education secretary calling for an immediate independent inquiry into what it has described as the A-level and GCSE “grading fiasco”.

The Association of School and College Leaders will write to Gavin Williamson warning him that there is an urgent need for a review following a chaotic week which has culminated in a government U-turn in the way both GCSEs and A levels are being awarded.

It has also warned that the government needs to put in place a contingency plan to help schools to cope if the coronavirus continues to cause widespread disruption in the next academic year.

U-turn: Teacher-assessed grades to be used for GCSE and A level

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The union’s general secretary, Geoff Barton, said: “There is an urgent need for the Department for Education to commission an immediate independent review which will rapidly establish exactly what went wrong with the process for awarding grades to A-level and GCSE students this summer, and to publish its findings and recommendations.

“This degree of transparency is necessary at a time when public confidence has been badly shaken.

GCSE and A-level results: ‘Public confidence has been badly shaken’

“It seems to be clear that the statistical model for moderating centre-assessed grades was flawed, and that it produced many anomalous results.

“But how did this happen? Why were the problems not foreseen? And why were ministers not on top of this?

“Most importantly, what lessons can we learn for the future? While the government plans for students to sit GCSEs and A levels next summer, there is currently no plan B if there is widespread disruption because of coronavirus.

“The government and Ofqual should be putting in place a robust contingency plan, drawing on the lessons from this summer’s debacle.”

England has followed Scotland, Northern Ireland and Wales in deciding to use teacher-assessed grades for GCSEs and A levels in England after all this year.

In a sharp U-turn from education secretary Gavin Williamson’s previous declaration that the use of teacher assessment “degrades every single exam result”, Ofqual announced yesterday that GCSE and A-level candidates can be awarded grades assessed by their teachers.

Students will now receive the highest grades from either their centre-assessed grade or their moderated grade from Ofqual.