By Sean Coughlan BBC News Online

Zainab Khan expected to be starting university this autumn.

But instead she is caught up in a dispute over A-level results, that by Monday had widened enough to merit an angry denial from the Prime Minister's official spokesperson.

A pupil at Colston's Girls' School in Bristol, Zainab had hoped to take up a place studying law at Bristol University.

If it was an exam, I'd be prepared to accept that I had done badly, but coursework, which has been seen by teachers, is different

Zainab Khan, A-level candidate

But while she performed strongly in her written exams, including 100% in one paper, her coursework for A-level Spanish and history scored only an E-grade.

This dragged down her overall scores and has meant that she has missed out on the grades needed for the place at Bristol.

The independent school, which had seen the coursework before submission, and which had confidently expected it to achieve an A-grade, is disputing both results and remains convinced that the marking is incorrect.

Stress

But for Zainab, this means either waiting for the appeals process with the possibility of going to Bristol next year - or taking a place at another university needing lower grades.

"This has been so stressful and I don't know who to blame," says 18-year-old Zainab.

"You read about this kind of thing, and think that it must be the student who hasn't performed well.

"And if it was an exam, I'd be prepared to accept that I had done badly, but coursework, which has been seen by teachers, is different," she said.

Head teacher, Judith Franklin, although reluctant to be drawn into any conspiracy theories, says that "something very peculiar" appears to have taken place with the marking.

The Spanish coursework, she remains certain, is of a much higher grade than the E-grade suggests.

An initial re-mark has not resolved the dispute, and the school has now appealed to the chief examiner of the OCR exam board.

'Insult'

And this has not been a one-off, as all the other pupils taking the exam from her school are also appealing about "very surprising" marking.

She says that is an "insult" to experienced teachers to suggest that they did not know the difference between excellent coursework and material rated as poor.

And she suggests that a practical explanation for inconsistencies in marking could be a shortage of experienced markers.

The number of exams taken by pupils has risen and she says this has added to the difficulties in finding markers.

And the use of inexperienced markers could contribute to the current spate of grading disputes.

In a case last year, the head said that a U grade, sent back for re-marking, had been given an A grade, suggesting that the problem was with the marking and not the teachers.

In last year's GCSE exam results tables, Colston's Girls' School was the top school in Bristol, with 100% of pupils achieving five or more good GCSEs.

It has achieved this maximum score in three out of the last four years.

At A-level, it was ranked at 10th place, out of 15 schools.

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