Leading universities are warning teenagers that they will not gain admission if they study “soft” A levels in the sixth form.

The universities are insisting that pupils take traditional subjects if they want to be considered for degree courses. Those applying with A levels in subjects such as media studies or health and social care would rule themselves out.

Up to one in six students took A levels this summer in at least one of 20 subjects listed by Cambridge as “less effective preparation” for entry. In what will come as a surprise to some schools and students, the list includes business studies, information and communication studies, and design and technology.

The move to spell out “unacceptable” A levels emerged after the pass rate rose for the 24th successive year to a record 96.6 per cent. The rise in the proportion of A grades awarded was the second largest in 40 years.

In a backlash against the growing popularity of subjects such as sports studies, and tourism and dance, institutions such as Cambridge, the LSE and Manchester are telling applicants to concentrate on the more academic A levels.

Admissions tutors insist that a lower grade in an academic subject, such as history or mathematics, will be of more use than a high grade in an apparently easier alternative. However, they believe that thousands of working-class pupils are losing out when they choose their A-level courses, because schools are failing to give them the best guidance. The proportion of state school pupils and those from low-income families attending university dropped to its lowest level for three years in 2004-05.

Tomorrow more than 700,000 teenagers will receive their GCSE results. Cambridge has posted a notice on its website telling youngsters: “Your choice of AS and A-level subjects can have a significant impact on the course options available to you at university.

“To be a realistic applicant, a student will normally need to be offering two traditional academic subjects. For example, mathematics, history and business studies would be an acceptable combination,” Cambridge’s online prospectus states. “However, history, business studies and media studies would not.”

Geoff Parks, the admissions tutor for Cambridge, said that a significant number of students were given no advice on what options might be closed to them if they chose a poor combination of A levels.

Last week it emerged that just 42 per cent of 18 to 30-year-olds in England were attending university in 2004-05, the second successive drop in two years. Few, including the Government, now expect to meet the target of half that age group attending university by 2010.

Generous bursaries for the worst-off and outreach programmes appear to be making little headway in encouraging students from poorer backgrounds to apply. Universities are baffled and the Government has ordered an audit.

Tessa Stone, director of the Sutton Trust education charity, which provides summer schools to encourage more underprivileged children to apply to university, believes that poor A-level guidance could be one reason. Dr Stone says that Cambridge’s direct approach may appear hard, but it is fairer to candidates in the long run because they are less likely to drop out if they have studied the right subjects.

While many universities do not explicitly exclude subjects, Dr Stone says, in reality they do. At Bristol, few A levels are explicitly discouraged, but for a BA in English, the prospectus states that GCSEs and A levels “in classical or foreign languages” are an advantage. In the same way, law A level is “acceptable but does not give any advantage”.

Malcolm Grant, Provost of University College London and chairman of the Russell group of research universities, said that students must not be put off learning, however.

“I do think universities must be more explicit than implicit in guidance, but they must also widen participation. There are also so many things that switch kids off and being advised to do subjects that don’t match their aspirations could be a disaster.”

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