Many are cutting back on their student teacher placements because so many experienced staff are taking early retirement.
The situation is so bad in some areas that teacher-training institutions have only found enough classroom places for their students because they failed to recruit up to target, a special hearing of the House of Commons education and employment select committee will be told next Tuesday.
In a personal submission to the committee, Nigel Gates, former chairman of the Association of University and College Lecturers, warns of "a very real crisis" in teaching recruitment and a "gradual dumbing down" of the quality of student teachers.
His evidence reinforces the submissions of the unions to the School Teachers' Pay and Conditions Review Body that urgent action is needed to stem a deepening recruitment crisis. The latest figures released by the Universities and Colleges Admissions Service in June showed applications for primary teacher training down by about 11 per cent. The average A-level score for teacher-traini ng courses was a C and two Ds.
"It is clear from this that teaching is not attracting the people it would have in previous years and ought to in future," says the joint submission from three of the teacher unions, published this week. "It is clear that teaching is not an attractive profession in the 1990s. The decline in teachers' pay relative to other non-manual workers is undoubtedly a major factor. Others would include the "teacher bashing" of recent years and the difficult working conditions."
The headteache r unions believe university tuition fees will only make the situation worse and has suggested a training wage for trainee teachers in their final year of university and the first of working.
Professor Charles Desforges, head of Exeter's school of education, believes that with the recession at an end, Government moves to reverse 10 years of bad publicity will not be enough to attract good candidates without better pay.
"There is a real struggle in getting people - it's nothing new, it just worsens every year," he said. "It's the devil's own job getting suitably qualified people to meet quotas. Whereas it used to be the shortage subjects were in physics, chemistry and maths, it's getting to be where every subject is a shortage subject - for example, modern languages is quite a problem."
Mr Gates' select committee submission says teaching, while still attracting quality candidates, is seen by many able students as a "fall-back" job.
As the pool of suitably qualified applicants shrinks, admissions tutors will come under increasing pressure from their institutions to recruit weak students to meet quotas and ensure funding, he warns.
"Some ITT admissions tutors may well be forced into accepting students that, under ideal circumstances, they would prefer to reject. Thus, instead of the quality of entrants being raised, which we all want, the current reality is that the quality is declining."
He believes that admissions tutors are still maintaining standards, citing an example of a tutor rejecting four secondary maths applicants as unsuitable, despite course vacancies.
Dwindling classroom placements are a new problem. He writes "Many schools have had to promote to fill gaps left by the wave of premature retirements and most newly promoted teachers are currently on a very steep learning curve. In a knock-on effect, this is impacting on initial teacher-training (ITT) institutions.
"I have been told by several people representing a range of ITT institutions that, as far as their PGCE secondary courses are concerned, it is fortunate that they have not met their targets because there would not have been enough places this year in the partnership schools to accommodate their students."
His findings were echoed by several schools of education, but the Teacher Training Agency and other teacher-training institutions - including Leeds University and Exeter University - say they have no evidence of early retirements affecting training placements.