The NAHT is calling for a review of plans for summer exams amid concerns that current adaptations are insufficient, Schools Week reports.
The call comes as official statistics revealed that pupil Covid absences had leapt by 30 per cent in the past two weeks, with many schools experiencing high teacher absence.
Students sitting GCSE and A-level exams this summer will be given a choice of topics and reference sheets in some subjects and in others they will know the main focus of the exam.
But the school leaders union says these plans now may not be enough, given that they were drawn up before the huge Omicron wave, which is still affecting schools.
Paul Whiteman, NAHT general secretary, said there needs to be “more recognition that some students could be disadvantaged by the gaps in their learning due to Covid disruption”.
“If the government doesn’t do more to acknowledge this, trust in the fairness of the examination process will falter.”
The union has said it wants advanced information published before February 7 and a decision to publish performance tables reversed.
An Ofqual spokesperson said it did recognise the disruption students had experienced, and an “unprecedented package of support” had been put in place.