Just 12,000 teenagers started studying diplomas last month - a quarter of the original prediction.

Ed Balls, the Schools Secretary, revealed the figures to the House of Commons today.

He said: “The latest information we have from local consortia indicates that around 12,000 young people are currently working towards a diploma.”

The Government initially estimated the new qualification, designed to bridge the divide between academic and work-based study, would be taken by 50,000 teenagers. This was revised to 40,000 this summer, then to 20,000 last month.

Diplomas will eventually be available in 17 subjects and four levels, but the first five themes were introduced at the start of this academic year - construction; creative and media; engineering; information technology; and society, health and development.

Schools will group together to offer the full range, which means pupils having to travel between different school sites plus workplaces.

Mr Balls was updating MPs on educational reforms for 14 to 19-year-olds.

He said: “My department has received much positive feedback from young people taking the new diploma qualification, describing how exciting and enjoyable they have found their studies, and from teachers who have been impressed by how successfully the distinctive new curriculum, combining theoretical studies with practical work based experiences, has engaged their students.

“Our focus continues to be on the standard of teaching of the diploma, and on supporting the system to build the capacity to deliver these reforms.”

Mr Balls said all of the Russell and 1994 groups of universities had agreed to consider applications from diploma students.

But he was criticised by his political rivals. David Laws, the Lib Dem schools spokesman, said: “The take-up of the new diploma has been a complete flop. The Government forecast that 50,000 young people would take-up this qualification, but we now learn that far fewer have done so.

“It is hardly surprising that take-up is this low because of the complexity of the system and the Government’s hopeless fudge of running the existing GCSE/A-level system alongside them.

“It is likely that the diploma will not become the qualification of choice for most youngsters until the Government makes a clear decision and establishes a simple general diploma for all students, in which GCSES and A-Levels would be building blocks.”

Michael Gove, the Shadow Children’s Secretary, said: “We want the diplomas to succeed as a high quality alternative to the academic route, so it is disappointing the numbers taking up the new qualifications are so far below ministers’ estimates.

“First they said they expected 50,000, then 38,000, then 20,000 and now we discover that just 12,000 are actually taking the new qualifications.

“Coming in the wake of the SATs fiasco and with Ed Balls currently embroiled in yet another administrative disaster over educational maintenance allowance payments, the confidence of parents and teachers in his department’s ability to deliver large-scale projects is rapidly disappearing.”

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