Thousands of GCSE English literature pupils set to receive their results next week could have their marks adjusted to take account of an error in the paper they sat.

The paper in question mixed up two warring families in Romeo and Juliet by wrongly implying that Tybalt was not a Capulet – forcing exam board OCR to issue an apology.

The question asked students: "How does Shakespeare present the ways in which Tybalt’s hatred of the Capulets influences the outcome of the play? Refer to this extract from Act 1 Scene 5 and elsewhere in the play."

Sally Collier, the head of exams watchdog Ofqual, warned earlier this week that she had the power to fine OCR over the blunder.

Now, ahead of next Thursday's GCSE results day, it has emerged that OCR has adjusted the marking scheme for the paper and that grade boundaries could be changed as a result of the mistake.

In a written update to schools, OCR chief executive Leo Shapiro said the exam board wanted to "reassure all teachers and students that their results will be accurate and fair".

He wrote: "We know the error has affected students’ performance in a variety of ways – not just on one question but across the whole paper."

The most frequent scenarios included answering the question literally – as it was written – or writing about Tybalt’s hatred in general. "A significant number" of students also responded to the question as it should have appeared, Mr Shapiro said.

The letter said OCR had "already adjusted the examiners’ mark scheme to reflect the different ways students answered the question", and that setting different grade boundaries was "one of the options we will consider" following an internal investigation, which Tes understands is ongoing.

In addition, the exam board will provide copies of the marked papers free of charge to all students who sat the exam. On results day, it will also provide a "short statement" for schools to give to each of those students who answered questions on Romeo and Juliet, "explaining the solution we applied to their paper".

'An unacceptable error'

The letter added: "If students and teachers are still not happy with their GCSE English literature result, they can request a review of the marking of the exam paper. For all students who answered one of the Romeo and Juliet questions, the review of marking will be free of charge."

The paper was taken by 14,000 pupils, but some of them may have answered questions on Macbeth, The Merchant of Venice or Much Ado About Nothing, instead of Romeo and Juliet.

Mr Shapiro ended the letter by stating: "This was an unacceptable error and we are very sorry for the impact on you and your students. As results day approaches, we know your students may start to feel anxious and we hope this letter will go some way to reassuring them."

Ms Collier told the Sunday Times: “We have been working very closely with OCR to ensure everything possible is done to minimise the impact on student performance. I want to return to this after the summer and, as a regulator, I may well want to take action.

"I have a range of powers at my disposal. I can fine them, investigate them or direct them to take a specific action.”

Separately, exam board Edexcel has written to schools about allegations that economics and mathematics A-level papers were leaked ahead of the exams.

Sharon Hague, responsible officer for Edexcel Qualifications, yesterday wrote that Edexcel was aware of a comment that had been posted on social media immediately before the start of the economics exam "making broad references to topics included in the examination but without any specific detail".

Following an investigation, involving interviews with the candidates involved, Edexcel remained "confident that no advantage was gained by any student", said Ms Hague. The student involved has been disqualified from taking qualifications this year.

The circumstances surrounding the maths A level were "complex" and subject to an ongoing police investigation, Ms Hague added. However: "Every student can...be confident that the grade boundaries were set fairly and that they can have confidence in their results".

Results had been withheld for a "small number of students", who face "malpractice sanctions". She added: "Where others may be included in the ongoing police investigation, we reserve the right to take action should any further individuals be subsequently found to have accessed the question in advance."

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