Alan Johnson’s chances of becoming Labour deputy leader take a serious blow today from a highly critical attack on one of the biggest changes to secondary education in the past 40 years.

Plans for the new job-related diplomas to run alongside A levels have been described as muddled, in danger of lacking practical content and being rushed through without being properly tested.

In a scathing report, the Commons Education Select Committee today accuses the Government of not being clear about the purpose of the qualification, the learning that it will involve and a failure to involve teachers and examiners in its development.

Mr Johnson, the Education Secretary, is frontrunner in the race for the deputy leadership and a champion of overhauling 14-19 education to keep more teenagers in school.

The specialist diplomas, the first five of which are to be introduced in September, combine practical work experience with academic study in an attempt to offer more relevant courses for teenagers.

They came about after Tony Blair refused to abandon the A-level “gold standard” in 2004 in favour of one overarching diploma to replace GCSEs, A levels and existing vocational qualifications. Instead, the Government proposed single diplomas in 14 subjects alongside A levels, from engineering to hair and beauty.

However, in spite of asking both business and universities to design the new qualification, critics have voiced fears that it will neither offer hands-on vocational training nor be sufficiently academically demanding.

The MPs lay the blame for this squarely at Mr Johnson’s door. “The Government describes diplomas as charting a middle course between vocational and academic learning, but it is far from clear that those in charge of developing the different diplomas share a common understanding of what they are for and what kinds of learning they will involve,” they wrote.

The select committee cautioned that there was still confusion about key aspects of the plan. Work to develop the diplomas had been “uncomfortably compressed”, and there were widespread concerns that they would not be ready.

Teachers, lecturers and exam boards also have had too little input into them and time to prepare for their introduction in schools and colleges next year.

“Too often in the past, initiatives have been rolled out in a rushed manner, with negative consequences in terms of quality,” the MPs said, adding that if more problems emerged during the first pilot, the rest of the scheme should be delayed.

They also raised concerns about the continuing lack of a clear grading system and content, which meant that few universities appeared prepared to take them seriously.

The comments come as a survey of 565 teachers and lecturers reveals that almost two thirds believe that the new diplomas will be seen simply as training programmes leading to low-paid, low-status jobs for nonacademic pupils.

According to Edge, the educational foundation which commissioned the research, only 3 per cent of teachers think that diplomas will appeal to middle-class students.

Teaching unions said that schools needed more money and training to prepare them for the qualifications, and that A levels should be brought into the structure to break down the barrier between academic and vocational qualifications.

What to watch

Key issues to look out for in the race be deputy leader:

Mentions of Iraq and America as candidates pander to the membership

Harriet Harman is married to union man Jack Dromey, which should help in the union section

Hilary Benn has the right name for the membership. His father, Tony, was always more popular with members and unions than with MPs

Note how the Blairite vote splits. Already John Reid and Tessa Jowell have gone for Hazel Blears; Miliband, Purnell and Baroness Sally Morgan for Johnson

Unions have backed Jon Cruddas with funding

See how the bookmakers’ odds change as the contest is widened to members and unions

Watch how Alan Johnson — the ex-postman who was once sacked from Tesco — plays to the unions

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