Tens of millions of pounds could be wasted every year training new teachers who fail to make it into the classroom.
A report this week showed that as many as a third of students, many of them on government bursaries, at some of the leading teacher-training colleges in England failed to gain qualified teacher status (QTS) after either dropping out or failing to pass postgraduate certificate in education courses.
It suggested that thousands of people were being tempted into doing PGCEs by the promise of government bursaries - now worth between pound;6,000 and Pounds 9,000 a year - but that many were unsuitable for the profession.
Professor Alan Smithers from the University of Buckingham, who carried out the study, said: "The common impression is that we are so short of teachers that anyone who enrols is guaranteed a qualification. But it is encouraging that universities and colleges are clearly exercising high standards and weeding out those who are not good enough."
Teaching is one of the few postgraduate courses that carries state-funded bursaries, worth pound;6,000-a-year, rising to pound;9,000 annually for shortage subjects such as maths and science.
Trainees also have their course fees - worth around pound;1,200 - picked up by the taxpayer, although they will have to make personal contributions of up to pound;1,800 from next month when controversial "top-up" fees are introduced.
The Buckingham university study - an analysis of data supplied by the Training and Development Agency for Schools (TDA) - showed that 13,312 people started training as primary teachers on university or college-based courses in September 2004, most of whom were doing a PGCE. However, 1,584, or 11.9 per cent, failed to qualify the following summer.
Meanwhile, there were 15,263 university-based secondary trainees - but 2,309 (15 per cent) failed to complete the course. Failure figures for the 9,146 students doing on-the-job training in schools were not known.
The failures represent a potential loss of up to pound;43.6m for the Government, assuming that trainees received their full pound;6,000 bursary andJtheirJpound;1,200 fees were paid. In addition, each university and college receives around pound;4,000 per student in "core funding" - moneyJintended to coverJother training costs.
But James Rogers, executive director of the Universities Council for the Education of Teachers, said the amount of money wasted was likely to be much less because most trainees who are failing courses drop out early. "It is right that students are counselled off courses if it transpires that they are not cut out for teaching," he said. "The figures would, in fact, be far higher were it not for the very rigorous recruitment and selection procedures adopted by teacher-training providers."
In all, 33,750 trainees qualified as teachers after completing college, university and school-based courses in summer 2005, a rise of 6 per cent on the previous year.
Many more trainees managed to find a job compared with previous years. Only 5.4 per cent of primary trainees and 2.7 per cent of those on secondary school courses were still looking for a teaching post in January 2006, six months after courses ended. This compared with some 10 per cent of all new teachers the year before.
Flunking the course
University teacher training drop-out rates
Highest secondary drop-out rates: Greenwich (37.8 per cent) Brunel (33.2 per cent) Goldsmiths (26.7 per cent)
Highest primary drop-out rates: Goldsmiths (33.7 per cent) Brunel (30 per cent) Hertfordshire (21.8 per cent)
Lowest secondary drop-out rates: Bishop Grosseteste (nil) Loughborough (3.4 per cent) Newcastle (4.5 per cent)
Lowest primary drop-out rates: Chester (1.8 per cent) Northampton (2.8 per cent) Leeds (4.5 per cent)