MANY of the country’s leading schools appear to be artificially bolstering their reputations by refusing to take weaker pupils in the sixth form and replacing them with high-flyers from other schools before their A-levels.

Extensive research by Ralph Lucas, editor of the Good Schools Guide, shows that while some top schools show great loyalty to the children they select at 11 or 13, others appear to be boosting their chances of getting good A-level results by quietly advising pupils at 16 to take their A- levels elsewhere.

Lucas, who obtained the data from the Department for Education and Skills using the Freedom of Information Act, suggested the study showed that parents could no longer rely on schools retaining children at 16 even if they were capable of achieving reasonable A-level results.

“A lot of harsh decisions are taken and they are being taken not in the interests of the child but in the interests of the institution,” he said. “The pressure is on schools to do well in the A- level league tables, so many have started resifting at 16. Many good schools don’t do this, but others are making pupils leave even though they could cope with A-levels.”

The data, which cover the 2,600 state and independent schools in England with sixth forms, show that at least 20% of fifth-formers in selective schools did not go on to do A- levels at the schools that gave them a place at 11 or 13.

However, there is marked variation. The 10 most “loyal” schools, which all retained more than 97% of their GCSE students in the sixth form, included Eton, St Paul’s, Ampleforth and Westminster.

At the other end of the scale, at Alderley Edge school for girls in Cheshire and Kingston grammar in Kingston upon Thames, more than a quarter of those taking GCSEs in the fifth form did not go on to take their A-levels at those schools.

State schools are just as likely to lose lower performing pupils after they have taken their GCSEs. The research showed 40 fifth-formers at the high-performing state grammar school, Queen Elizabeth school in Barnet, north London, did not make it into the sixth form.

The figures do not detail exactly why pupils switch schools at A-level and schools insist there is no policy of “culling” weaker pupils.

John Marincowitz, headmaster of Queen Elizabeth’s school, said between 30 and 40 boys in the fifth form did not stay on to do A-levels, but denied that most were “weeded”.

“Some win scholarships to independent schools,” he said. “Others are advised we do not think their performance at the school would allow them to do certain A-levels. It is a very small number that do not get offered places in the sixth.”

Andrew Grant, headmaster of the independent St Albans schools in St Albans, Hertfordshire, said pupils left at 16 for different reasons: “Some parents take a financial decision to switch to a state sixth form or state sixth-form college. Others move away from the area and some want courses not offered here.”

The headmaster of one independent school, who did not wish to be identified, said some schools insisted that A-level students had to have at least four grade As at GCSE: “There are schools that set requirements above what is educationally necessary to survive at A-level. They would say it is more effective to teach students who are roughly the same ability level. They don’t want the ones that tread along the bottom. But we all know that if you have clever pupils, you improve your results by losing the dimmer ones.”

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