New teachers have poor knowledge of their own subjects and are being failed by training colleges, according to leading academics.
A study this week says the system for training most new teachers in universities should be replaced by school-based courses.
Too many teachers are accepted on to courses without proper grasp of subjects, says the report by a group which includes Chris Woodhead, the former chief inspector of schools.
Colleges can decide how much specialist knowledge trainees need. But the study says that all primary trainees should have A-levels in the subjects they will teach and be educated to a decent standard in English and maths.
Secondary teachers should have a full degree in their specialist subjects.
Comparing Standards: Teaching the Teachers, published by Politeia, the right-wing think-tank, said recruitment and training were swamped by bureaucracy and driven by "irrelevant targets".
Professor Woodhead criticised claims by David Bell, the current chief inspector, that colleges are now producing the best-trained generation of new teachers.
He said: "I have always been sceptical of reports produced by Her Majesty's Inspectors and Ofsted's teacher training division. Too many of the inspectors in this team were a product of the teacher training world; too few were prepared to question their own deep-seated assumptions."
Last year more than 40,000 people started teacher-training courses in England, the highest number since 1973. Of those, 85 per cent were taken on to postgraduate and BEd courses and the remainder on school-based programmes.
Another of the report's authors, Professor Alan Smithers, based at Buckingham university, said half of the trainees were not in teaching three years later.
"In some cases, undoubtedly, the shock of the difference between university life and the realities of the classroom will be too great to bridge," he said.
He said a greater proportion should be taken on to school-based training, where as many as 85 per cent were still in the classroom after three years.
A Teacher Training Agency spokesman said that in a survey 84 per cent of new teachers rated their training highly. He added: "Ofsted's annual reports over recent years have pointed to the improving classroom performance of newly-qualified teachers. All initial teacher training includes a large proportion of in-school training."
Comparing Standards: Teaching the Teachers is available from Politeia, 22 Charing Cross Road, WC2H 0QP, price pound;10. Inspection of the key stage 2 training element of key stage 23 courses: 2002-4 is available from www.ofsted.gov.uk