Some 31,000 people registered for teacher training courses last year - a 12-year high, according to the Teacher Training Agency’s findings last December. And interim figures for 2003-04 show a further increase in trainee numbers of 15 per cent.

Now a new survey by the University of East Anglia explains these trends. Dr Anne Cockburn and Terry Haydn asked 194 trainees about their motives and expectations. The responses reveal much about why people choose to join and why they leave.

So what draws new recruits? The study found that trainees sign up because they want to nurture children and work with others. This perception of teaching’s ethos was enhanced by golden hellos and the “Those who can, teach” advertising campaign. By highlighting what teachers like about the job, the study offers clues about how to attract more people. It seems trainees get job satisfaction from having a hand in children’s progress.

The authors believe this finding should be emphasised in future.

A quarter of respondents say they get satisfaction from working with colleagues. Answers cite “comradeship” and “teamwork” frequently. Despite this, reform often focuses on individual performance. Cockburn and Haydn argue that advertising more in tune with these “job satisfaction” findings might tip the balance for prospective teachers.

Trainees also get job satisfaction from teaching per se (18 per cent), and the “friendly climate” in schools (10 per cent).

The study also reveals a lot about what trainees don’t like. Way out in front is the admin and red tape, cited by 88 per cent.

“We need to pay attention to this!” says Terry Haydn. “Some of the best teachers I have ever come across left the classroom due to bureaucracy and paperwork.”

This was a significant factor for those thinking about quitting their training.

“The bureaucratic nature of teaching is creating an unrelenting workload,” says one respondent. “I understand why 40 per cent of trainees leave the profession within three years.”

Close behind paperwork are concerns about pupil behaviour (45 per cent), workload (37 per cent), poor teaching resources (17.5 per cent), class sizes (12.5 per cent), lack of support (12 per cent), covering absent colleagues (6 per cent), policy changes (7 per cent) and too much testing (3 per cent).

So has the Government done enough to combat such disincentives? Recent strategies have aimed to improve teachers’ work-life balance. The Department for Education and Skills has put a 38-hour limit on the cover teachers can be expected to perform annually. And 10 per cent of a teacher’s working day is to be put aside for preparation and marking.

There is also an official ban on 21 administrative tasks - such as collecting dinner money, investigating student absence and doing bulk photocopying - which has been written into all teachers’ contracts. But this has been contentious.

The National Union of Teachers has refused to sign up to the ban, even though it advises its members not to do those tasks. The union is concerned that funding shortfalls in schools could mean that money for essentials such as books and equipment will be used to hire clerical or support staff instead.

“We have taken the list of things that the Government says teachers shouldn’t do and told teachers not to do them,” says a spokeswoman. “Our members need a better work-life balance, but at present the funding is not there to achieve that.”

In another move, the Government plans to expand the role of teaching assistants to reduce teacher workload. This has been welcomed in some quarters, but repudiated by the NUT. The union argues that the introduction of classroom assistants devalues the training invested in teachers.

“If you have spent the past fours years getting qualified, and are now being told that anyone can come in off the street and do your job, what’s the point of training?” says the spokeswoman. “What the Government is doing will ultimately damage recruitment and retention of young people at a time when we already have a massively ageing profession.”

But despite union objections, the study found that trainee teachers were positive about teaching assistants.

“I have worked in teacher training for 10 years and have never found any antipathy towards them,” says Terry Haydn. “Of the 194 surveyed, 29 said learning support would improve their working lives. Student teachers do not always make optimum use of teaching assistants, but they would rather have one in the classroom than not have one.”

Trainees say morale and job fulfilment could be improved by reducing class sizes (19 per cent), and providing better teaching resources (12 per cent).

But the authors say that the schools budget crisis has forced schools to move in the opposite direction. In the past year, the standing fund grant and the class size reduction grant were both removed from school budgets.

So how likely is it that trainees will stay? Not great, the survey finds.

Only 64 per cent of respondents say they see themselves still teaching in five years. For them, staying would depend on whether they enjoyed the job.

In short, they are unlikely to stay if current levels of bureaucracy and stress are not reduced.

It is sobering to find that 11 per cent of trainees plan to teach abroad within the next five years. Cockburn and Haydn believe this is a “worryingly high proportion”, especially as greater global competition for teachers is predicted for the coming decade. A further 10 per cent say they will be in other areas of education or outside it in five years’ time.

“Retention is a problem, with people often staying in schools for only two or three years,” says Terry Haydn.

Earlier this month, school standards minister David Miliband said the rise in teacher recruitment showed that government measures to attract more people “are taking effect and are on the right track”. Maybe. But what about the drain of teachers out of the profession? In that respect, the omens are not bright.

Anne Cockburn and Terry Haydn’s Recruiting and Retaining Teachers: understanding why teachers teach will be published later this year