Helen Williams, High Mistress of St Paul's Girls' School in Hammersmith, west London, said she faced professional ruin after alienating some influential parents with proposals to restrict the number of GCSE examinations sat by students to seven, supplemented by more demanding courses set and assessed by the school.
Parents and staff at the pounds 5,000-a-year school were divided over the changes, introduced a year ago, and the governors lost confidence. Despite a spirited defence of her plans, in public to parents and in private to the Mercer's Company governors who run the school, Mrs Williams resigned after what she called 'two months of sheer hell'.
Her departure after less than three years in the post was announced 'with great regret' by the governors to parents less than three weeks before the start of term. Henry Palmer, chairman of the governing body, said in a letter to parents at the weekend: 'The governors would like to record their appreciation of the commitment and contribution which Mrs Williams has made to the life of St Paul's Girls' School during the past three years.' Parents were promised more information soon.
Guidebooks describe the school's academic reputation as 'formidably high-powered' and 'amazing'. Almost all leavers go on to degree courses, 36 per cent to Oxbridge. Famous old Paulinas, as they are called, include Shirley Williams and Shirley Conran, the author of Superwoman.
Intensely selective, the school steers virtually all girls through GCSE, more than 91 per cent of them at A or B grades. When it comes to A-levels, more than 98 per cent pass, 75 per cent at A and B grades.
Mrs Williams and other heads of highly academic independent schools such as Winchester or Manchester Grammar have argued that, with such students, GCSE becomes an 'irrelevance'.
But as a self-confessed idealist who believes that children should be taught to work for the intrinsic merit of the subject and not just for examinations, she has been less cautious than other heads in promoting her proposals. She underestimated, it seems, the demands of fee-paying parents for qualifications for their children in her pursuit of breadth and education for life.
Sitting in the upstairs drawing-room of the high mistress's house overlooking the school, Mrs Williams is clearly bitter and hurt by the experience. She is incensed by press coverage of the affair, including a claim that she was booed by pupils during her speech to parents and governors last term. Completely untrue, she says.
Mrs Williams admits now that her proposals in March 1991 took parents and governors by surprise and might have been better presented. She proposed a limit of seven GCSEs as a balanced core: English language and literature, mathematics, Latin, a modern language and dual science.
In addition, girls would take information technology and three courses designed and assessed by the school from a choice of history, geography, art, music and a second language.
The governors backed Mrs Williams but their decision to phase the changes over two years led to divisions among staff and parents, she believes, although many supported the move.
'The whole thing grew into a crisis. Once there is any chink in the armour of confidence it draws all dissidents. It meant a year for reservations to increase and solidify. I think it led to factions, which was very unfortunate. People lose confidence very quickly if things are not definite and it could not be definite when it was staggered over two years. I'm all too aware that one can teach efficiently and get terrific results by teaching to exams. As this school has the privilege of selecting among the cleverest girls in London, one should ask more than that and train them to work not just for exams,' she said.
In her speech, Mrs Williams spoke of the need not to cram too much of everything into too little time and defended her 'modest proposal', which seemed to have been 'perceived by some as a most serious threat and an attack on GCSE itself'.
She added: 'I underestimated the anxiety of the age and for this I am deeply sorry, for I hold nothing more dear than the responsibility of the school to enable all its students to realise their proper aspirations.
'However, nothing will change my commitment to the idea that a truly liberal education is much more than the sum of external examination syllabuses,' she said.