A THIRD of the 7,000 sixth-formers who sat the first world-class tests this week were from private schools, who educate just 7 per cent of the nation's pupils.
Students sat new Advanced Extension Award (AEA) papers in 16 subjects. English, maths and physics had most entries.
Papers in popular subjects such as psychology and sociology are not available. There are also no tests in vocational subjects.
The award, aimed at the brightest 18-year-olds, was introduced to help universities distinguish between straight A- grade students.
But the exams, which cost more than pound;1 million to develop, were sidelined before their debut when government plans for a distinction A-level were revealed as part of the 14 to 19 reforms.
There has been strong opposition to the Green Paper proposal, and the Government's own exam watchdog believes the distinction A-level would destroy the integrity of existing grades.
Instead, the Qualifications and Curriculum Authority wants AEAs to be given a chance - despite the over-representation of private schools in the first sitting.
A spokesman said: "With proper promotion, AEAs could be more successful than the Special Papers they replaced. Provisional entry numbers have been reasonably encouraging."
Teacher unions said the entry figures proved that AEAs were a low priority for most schools. John Bangs, head of education at the National Union of Teachers, described them as "an irrelevance".
Universities have, on the whole, been lukewarm. Alan Ryan, warden of New College, Oxford, said there was so little information from the QCA about who was taking the papers, they did not feature in offers to applicants.
"If everyone had the chance to do them they could be useful but that is clearly not the case," he said.
Cambridge University has encouraged students to take AEAs but will not make them part of an offer. At Chelmsford high school for girls, a grammar and technology school, 10 pupils sat the biology AEA without extra tuition.
The awards should not require any additional teaching but pupils at schools which can offer coaching are most likely to take them. Each award costs around pound;25.
Monica Curtis, headteacher, said: "The difficulty is that some schools can afford to set aside time and staff to coach pupils and others cannot."
For a distinction A-level pupils would be able to choose whether to answer more difficult questions, which would be included in the main papers. Supporters of this option say that this would give everyone the same opportunity to shine. But critics argue that students should not be forced to decide under pressure whether to go for a distinction.
Downing Street's favoured option is the A* which would be awarded to the top 5 per cent of candidates. The QCA said that this proposal would work better than a distinction A-level. It also prefers the alternative of reporting marks alongside grades - a system which the Secondary Heads Association and many university admission tutors support.
These approaches, however, fail to stretch able candidates with more challenging questions.