A school has banned a grade A pupil from its end-of-year prom because her parents would not force her to attend extra revision classes.

Kayleigh Baker, 16, a prefect at Hurworth School, in the Prime Minister’s Sedgefield constituency, is a model student with a 100 per cent attendance record and a series of outstanding annual reports.

Last year, she achieved A grades in two GCSE examinations that she had sat a year early and is expected to achieve top marks in nine subjects this summer.

Her invitation to next month’s prom has been withrawn after a dispute between her parents and the school’s senior management about its demand that Year 11 pupils should attend compulsory after-school revision sessions.

The annual event, which will be held in an 18th century country manor house, is the highlight of the school’s social calendar and for many pupils represents the climax of their school career.

Dean Judson, the head teacher, has also barred Kayleigh from the netball team and from going on any school trips. He allowed her to attend a recent achievement ceremony, at which she collected five awards.

Kay and Ellis Baker say that their daughter is a talented and diligent student who does not need the extra burden of two weekly, hour-long revision lessons at the end of the school day.

They believe that they have the backing of the Department for Education and Skills, which told them in a letter: “All study support (out of school hours) activities are entirely voluntary and there should be no compulsion on young people to attend.”

One of Hurworth’s governors has resigned in protest at its “severe and extremely punitive” treatment of Kayleigh, who hopes to become a lawyer, but yesterday the school, near Darlington, Co Durham, showed no sign of backing down.

Eamonn Farrar, its chief executive, said: “We know what’s best for the children and that is why we make them go to these lessons.” If one pupil were allowed to miss the sessions, others would soon follow suit, he said.

“In life, if you don’t do something you are asked to, then you can’t expect anything in return. Children who don’t conform to the school rules cannot expect to go to the school prom.”

The 636-pupil school, for children aged 11-16, has won praise from Ofsted inspectors for its “very good leadership and teaching”, which has led to a significant recent improvement in its GCSE results. The proportion of pupils achieving five or more A*-C grades rose from 39 per cent in 1998 to 93 per cent last year.

Mr Farrar denied that the introduction of compulsory after-school lessons was prompted by an unhealthy obsession with school performance tables.

“If I said I run these classes because of the league tables, that would be immoral. We don’t play the league table game — we just celebrate when we top them.”

Kayleigh, described in a recent school report as “an inspiration to others with impeccable behaviour and a totally focused attitude”, said that she was deeply disappointed by the school’s decision.

Her dress, handmade for her in China last year, was inspired by the gown worn by Kate Hudson in the Hollywood film How To Lose A Guy In 10 Days. Kayleigh had a companion to go with and said that she had been “looking forward to the prom all year”.

Boys wear black tie and the girls full-length gowns, and many will be travelling to the Hardwick Hall Hotel, near Sedgefield, by limousine.

“Everybody has been talking about it, getting excited. My friends are talking about their dresses and asking each other where they got their shoes from, and I can’t join in,” she said.

“I’ve been excluded from everything fun at school, everything that I enjoy. It’s cruel and I feel like I’m being punished when I haven’t done anything wrong.”

Kayleigh said that, by passing her religious studies GCSE a year early, she already had five free periods in her timeta-ble that were allocated for revision. As a result, she did not need the after-school sessions.

Her father, a health and safety consultant, said: “All children that age need balance. Kayleigh is studious and conscientious. We made a decision about her welfare and the school has punished her for it.”

Mrs Baker said that her daughter had been so upset that she had lost a stone in weight.

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