Teenagers who do better than expected in their A levels have little chance of getting into leading universities under a new government system.

Universities and political opponents said that the “adjustment period” introduced this year was a mirage since many desirable courses were already full.

The five-day period is supposed to give school-leavers with higher than expected grades the chance to “trade up” to popular courses or prestigious universities, without losing their first-choice place.

More than 50,000 extra people have applied to university this year, but there are only 13,000 more full-time undergraduate places. The number of spaces in clearing is expected to be half of the 43,000 available last year.

Times Archive, 1976: Fall in 'A' level standards

If standards are falling the fact is being suppressed. Nobody is served, least of all the candidates, by its concealment

• 'A bad test for university selection', 1977

• Keep A levels, 1974

Guide to Clearing: essential information on universities in the clearing system

John O’Leary outlines some of the pros and cons of 40 UK universities likely to be offering the most places through clearing this year

• Act fast to snap up a university place through clearing

• Full universities leave A-level winners unable to trade up

• A degree of control over your future

Related Links

• Pupils with three A grades double under Labour

• No reason to celebrate

Multimedia

• EXPERT: Clearing guide, in full

• IN DEPTH: Good University Guide 2010

• Good University Guide

• School Gate blog: helping you through the maze of education

Those who are unfairly marked down in A-level exams could lose their place, even if they successfully appeal and later get a higher grade. Some courses are closed to British applicants even though they still have places for foreign students. This is because for financial reasons the Government restricts the number of British students that universities can recruit. Overseas students pay higher fees and do not receive the grants or subsidised loans available to home students.

A spokesman for Surrey University said: “The Government is encouraging us to take more international students. We would like to take more home students but we have to abide by regulations. We are full for home students but have spaces for international students.”

Sussex University has separate clearing for UK/EU students and overseas students. Some courses at York University are available only for foreign students. It has about 100 places left for British students, compared with 350 this time last year.

Hull University’s website said: “Publicly funded universities and colleges are required by the Government to limit the number of students that are eligible to pay fees at the ‘home’ rate.”

Durham University said those who missed their grades, and later successfully appealed against the mark, could still miss out — unlike last year.

Other universities said that they had no way of knowing how the adjustment period would work. Glasgow has a handful of clearing places and none available for the adjustment period.

Leeds University said: “We do not anticipate that many adjusters will find suitable courses at this stage.”

David Willetts, the Shadow Universities Secretary, said: “Ministers have sown the seeds of failure for their own policy. Telling people they can trade up when there is a record number of applicants and when universities are already at risk of being fined for over-recruitment is a recipe for disaster.”

David Lammy, the Universities Minister, said that the adjustment period was a trial, which raises questions about its future.

He told The Times: “It is a more competitive year and demand is up but there’s absolutely no doubt that there will be more young people accepted by universities than ever before.

“Clearing will be competitive but I’m quite sure many universities will be offering places.

“We’re trialling this new adjustment period to allow young people to hold the offer they have and see if they can get into another institution or on to another course.”

Mr Lammy said that every year, two fifths of those who did not get a place in higher education applied the next year, and four fifths of those were successful. He saw no reason for this to be different this year or next.

However, this could create a backlog, exacerbating problems next year.

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