She left teaching after her first year, and spent five years working as a museum learning co-ordinator, followed by a stint as a teacher in Peru and working at an orphanage in Mexico.

Eventually, last year, she decided to return to the profession. “I always knew it was something I’d want to come back to. And on holiday that summer I just had an epiphany and realised that I wasn’t doing what I was meant to.”

She began applying for jobs, and was lucky enough to get an offer from one of her first four applications. This term, she started as a geography teacher at Wright Robinson Specialist College, Manchester, an 11-16 specialist arts and sport school.

“It is just fantastic,” says Charlotte. “Nothing beats the buzz of the classroom and the rush between lessons. Coming back is the best thing I’ve ever done.”

At the last count, more than 5,000 teachers returned to teaching in 2005-06, according to the Department for Children, Schools and Families, many after taking breaks to bring up children, travel abroad or simply to pursue other careers.

They made up 13 per cent of new entrants to the profession. But the outlook for them is getting bleaker. Back in 2001-02, returning teachers accounted for 22 per cent of new recruits.

With the job market getting more competitive, and with only 60 per cent of new teachers in full-time work by March of this year, the returner who doesn’t think tactically about how and where to apply could risk getting squeezed out.

“At the moment we probably have more people coming out of training than there are jobs,” says Professor John Howson, a recruitment analyst at Oxford Brookes University. “New teachers are more up to date with the latest initiatives and pedagogical methods, and probably cheaper. With school rolls falling and budgets down, why would you employ the more expensive person?”

Professor Howson emphasises the situation isn’t the same countrywide. In shortage subjects, such as maths and science, and in dense urban areas, such as London, it will always be easier to land a post. But in primary schools, and in competitive areas such as the rural north, the situation remains tough.

One way to make yourself more marketable is to take a returners’ course, which will refresh your knowledge of the curriculum as well as providing you with a short-term teaching placement.

“It definitely puts you further up the list, as far as heads are concerned,” says Debbie McGlone, manager of teachers’ employment agency Education VIPs. “The downside is it can be tricky to get on one and you need to apply months in advance.”

But the fact that such courses are free, come with a pound;1,500 bursary, and get some recent teaching experience on your CV are enough to tempt more than 1,000 teachers a year to take them. “It’s about making a smooth transition,” says Tony Cook, managing director of EM Direct, one of the biggest providers of returners’ courses, who estimates that 70 per cent of his students find teaching work within six months. “There have been a lot of changes in recent years: the renewed primary framework, 14-19 reforms, the key stage 3 curriculum and technology, so there’s a lot to catch up on.”

However, he emphasises that returning teachers have a great deal to offer employers. “They are coming back in to the classroom with life experience. Quite a few have travelled the world and lived in other countries and they can bring something a little different to their school.”

One such teacher is Alan Robson, 57, who has found a place as a design and technology teacher at Manor Park Community School in Nuneaton, Warwickshire, after spending 18 years managing a furniture factory in South Africa following 13 years of teaching.

“It was a wrench leaving teaching in the first place but when I was tempted into industry it was by an offer I couldn’t refuse. A fabulous salary, a BMW. All the things that teachers don’t get,” he says.

Eventually, after losing his job and finding it difficult to get more work in South Africa, he returned to his home town and ended up getting supply work at the very school he attended as a boy, and where he previously worked for eight years as a teacher. While two members of staff remain from his first stint as a teacher, the curriculum has changed.

“In my day all the classes were set. And there was no design and technology. It was woodwork and metalwork, with more emphasis on the practical side. Going on a returners’ course helped me to catch up with all that,” he says.

He sees his 18 years abroad as an asset. “Oh yes, the stories come out a lot. How many teachers can talk from experience about mass production? Or know how much a company can save just by cutting half a penny off the cost of a screw?”

But getting heads to see your potential is not so easy for everyone. Corinne Austin, 35, is working for a vocational training company after returning to teaching last year on a temporary contract. The contract ended, but despite a flurry of applications, she has yet to land a post.

“I did contemplate supply, but I have two children and need a regular income. The heads I’ve spoken to have all been positive, and say I’ve demonstrated commitment by returning to teaching. However, it still hasn’t got me a job,” she says.

As an aspiring primary teacher in east Yorkshire, Corinne has hurled herself into a particularly competitive marketplace. Sian Nixon, 30, also Yorkshire-based, knows how hard it can be to get noticed. “I applied for about 25 jobs and wasn’t getting anywhere. In the end I walked round to my local school and said I was looking. A week later, one of the teachers went on long-term sick leave and they rang me.”

Now a Year 2 teacher at Leconfield Primary School in Beverley, Sian admits getting to grips with technology has been a particular challenge. “That was a bit of a learning curve, especially interactive whiteboards. I’ve never used one before and had to practise on my own.”

But by keeping abreast of the local labour market, being proactive about getting experiences and making applications, it is possible to get back into the job you love. And your experience outside the school can come in quite handy.

Debbie Logan, 49, quit her job as a home economics teacher seven years ago to start her own company organising children’s parties.

The business didn’t work out, but the party plates still come in useful now she’s back in teaching, at Scissett Middle School near Huddersfield in West Yorkshire. “I use them for the end-of-term celebrations,” she says

How to get back into teaching

- Going on a returners’ course will get you up to speed with changes in the curriculum. See www.tda.gov.ukteachers returners for courses in England and Wales. For Scotland, contact your local authority.

- Doing supply work will satisfy schools that you have recent experience and get you known to heads.

- Be proactive about marketing yourself. Send your CV round and introduce yourself to local schools.

- Know your local labour market. Where are the skills shortages?

- Make the most of any recent experience with children and emphasise your proven track record as a teacher.