Almost one in three academies is failing to reach the minimum government target for GCSE results, despite benefiting from millions of pounds in public funding.

Ed Balls, the Schools Secretary, suggested yesterday that time was running out for older academies to improve while setting a deadline for them to transform their results.

Exam achievement has stalled or even regressed at some academies, with only a small number achieving the Government’s target of 30 per cent of pupils achieving five good GCSEs, including English and maths. It was missed in this year’s exam results by 40 out of 130 established academies, Mr Balls disclosed.

Tony Blair created the academies, which are semi-independent state schools with private sponsors and freedom from local authority control. The first three opened in 2002. Most built since then have replaced failing schools in inner city areas. The programme has recently gathered pace, with 200 open to date and another 200 planned.

In total, 270 secondary schools have been placed under the Government’s National Challenge programme, for missing the 30 per cent target — to be met by 2011.

Schools within the programme are entitled to extra funding but are monitored closely and set deadlines for improvement. Forty of these schools are academies, of which 10 have been open for at least three years.

Where an academy is not making satisfactory progress, the department would work with sponsors to “secure whatever changes are necessary to accelerate progress”, he said. This could include a change of leadership, a new partnership with a successful school or a different sponsor.

Some academies have shown remarkable results, giving a new start to schools in deprived areas.

But detractors say that this could be achieved with a change of leadership, without the need for academy status.

Christine Blower, general secretary of the National Union of Teachers, said: “The continued assertion that the academies programme is the magic solution to educational achievement does not bear up to scrutiny and makes a mockery of Ed Balls’s obsession of ploughing on with this expensive and unnecessary scheme.”

A report by the Public Accounts Committee in 2007 said the average cost of setting up an academy was £27 million — £5 million more than a normal secondary school. Some have cost as much as £35 million. Alasdair Smith, the national secretary of the Anti Academies Alliance, said: “This confirms our argument that academies are not a magic bullet to solve problems for schools. They have the same problems as community schools — yet they are paid vast quantities of taxpayers’ money and given preferential funding.”

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