Now new government-sponsored research is urging teacher-training programmes to respond to their emotions when assessing their needs.
For some would-be teachers the experience is overwhelming, others simply love it, but most of the almost 5,000 trainees questioned agree the process is highly emotional.
Researchers from Leeds and Nottingham universities and the MORI Social Research institute found a number of coping strategies. Some trainees develop an "off the peg" teacher persona when first entering the classroom, but realised later it was more important to be themselves.
"Bringing in your personality to the teaching role is part of how you teach," said a primary graduate teaching programme trainee in her early 30s.
Others tried at first to become friends with pupils but then found they needed to adopt a more authoritative approach.
Some initially relied on lesson plans and worksheets. "It was essential because I was so nervous. I needed the plan so I knew exactly what I was doing," said a secondary languages trainee in her 20s.
The research for the Department for Education and Skills is based on the findings of a questionnaire completed by 4,790 trainees completing their course in 2003-04, and in-depth interviews with 85.
The biggest factor influencing their decision to begin teacher training was a desire to help young people to learn, followed by wanting to work with children or young people and being inspired by a good teacher.
Trainees on the graduate and registered teacher programmes and those following school-centred courses were more confident that the training would help them become efficient teachers.
Stories about poor teacher morale failed to deter more than a quarter of respondents who cited it as an attraction, compared to 22 per cent who said it was a deterrent. The salary put off a fifth of respondents. Other deterrents were the public perception of the profession, speaking to other teachers and spending more time in higher education.
But again all four factors proved to be attractions to a much larger proportion of trainees.
The only factor that deterred more trainees than it attracted was the depiction of teachers in TV dramas such as Grange Hill, Teachers and Hope and Glory. Even then, though, the majority said it had no effect.
Becoming a Teacher: Student Teachers' Motives and Preconceptions and Early School-based Experiences During Initial Teacher Training, Hobson and Malderez (eds.), Kerr, Tracey, Pell, Tomlinson and Roper