The rural town of Boston, Lincolnshire, on the edge of the Fens, has long been distinguished for having the largest parish church in Britain - St Botolph’s, known locally as the Boston stump for the soaring tower that dominates the flat, cabbage-studded landscape. Now the town, population 55,000, has another distinction in the shape of 27-year-old Kirstyn Doherty, Britain’s youngest headteacher.

Appointed head of the 172-pupil St Mary’s RC primary school last summer, Mrs Doherty took up the post in September, having already spent seven years at the school - as a pupil. Looking suitably fresh-faced and wearing a blue trouser suit, Mrs Doherty could pass for 18 if she weren’t sitting in the headteacher’s office. But St Mary’s can’t take credit for inspiring her to want to be a teacher - that ambition was formed earlier. “Mum’s got photos of me scrawling on a blackboard at about three,” she says. “My younger sister had to endure lots of ‘lessons’. I was fairly disciplinarian at that stage.”

Sharp-eyed reception teachers might have spotted her then as the girl most likely to make rapid progress in something. “I loved school. I was a bit of a teacher’s pet really - bell monitor, in charge of the children’s school bank. I had plenty of friends and played a lot of sport but I was a hard worker.” She is still a hard worker. Having left Boston high school for girls with A-levels in English, French and Spanish - chosen with a teaching career in mind - she went to Bishop Grosseteste teacher training college in Lincoln, part of Hull university, where she did a four-year BA honours degree in English and teaching with qualified teacher status. By the time she graduated at the age of 22, she had already secured her first post at the 450-pupil Staniland primary school, also in Boston.

Since then she has added a masters degree - in primary education, specialising in management and teaching - and the national professional qualification for headship (NPQH) to the framed certificates hanging on her office wall. The NPQH - which by 2002 will be a requirement for anybody applying for a first headship - was a great help in her rapid rise through the ranks, she says. “It’s bringing education into line with industry. You need to be trained to run a school now, and they are looking for a different type of person, which is why age no longer matters. You have to be an accountant, an administrator, and a good communicator and facilitator of the information you’re given from government. As opposed to running your school your way, it’s now a national way.”

Kirstyn Doherty took a fast track through the NPQH course because of her masters degree, doing it in one year instead of the usual two. But she still had to undertake compulsory modules in accountability and strategic leadership, and learn how to set a school budget. These skills have proved useful, she says. “There’s not a day goes by when I don’t refer to something I learned on the course.”

In the packed dinner hall of St Mary’s, she wears her authority lightly. She moves from table to table, responding to raised hands, hearing about wobbly teeth, Grandad’s birthday, and, from one worried girl, a conflict between a forthcoming netball match and a planned family trip to Cyprus. Mrs Doherty - a keen player herself - promises to rearrange the match. Colleagues old enough to be her mother have a word in passing, before she hands out a “Headteacher’s Award” sticker to every child on the quietest table.

It wasMrs Doherty’s first boss at Staniland, headteacher Peter Long, who enabled her to bloom early in teaching. After she had spent a year in the classroom teaching Year 1, he asked her to apply for a new post setting up the school’s nursery unit. She got the job - and her first taste of management. “I had to set it up from scratch, interviewing nursery nurses and making decisions about the budget. It was quite an experience. I began to realise I would enjoy all the other aspects in school.”

After one year of running the nursery unit, she joined the management team, and helped guide Staniland through an Ofsted inspection in her third year. She rounded off her teaching experience by going back into the classroom - she taught years 2 and 6 and was put in charge of key stage 1, before applying for the post of deputy head at North Kelsey, a small school in the north of the county. From there it was back to St Mary’s.

No staff remain from the days when Mrs Doherty was a pupil at St Mary’s, although she says “it wouldn’t have worried me” if there had been. Her new headship is not her first taste of managing people older and arguably more experienced than she is. “It’s something I’ve had to deal with in a sensitive way almost from the start,” she says. Before she left Staniland, she found herself managing the person who had been her mentor as a newly qualified teacher, in her role as key stage 1 co-ordinator.

Her deputy head at St Mary’s, with 10 years in the school, also applied for the headship. How does she cope with the situation? “People have been very good about it and I’ve never had a problem. I was aware of the situation and made sure I was sensitive about it, and others helped.” Long phone calls and planning sessions over the summer holidays helped smooth things over before the start of term.

What she lacks in years, Kirstyn Doherty makes up for in a settled and assertive presence. There are no concessions to youth in her manner, although there may be in the teddy bear and whimsical pottery hedgehogs on the shelf in her office. Did she ever feel daunted about coming back to her old school as headteacher? “The day before the first day of term it suddenly dawned on me what I was coming into,” she says. “There was a nervousness, that it was going to be me that was running the show, but a good nervousness. I know the job can be lonely. But the staff are so supportive of what we’re trying to do together.”

She has not been afraid to make changes, beginning with observing each of her eight teaching staff in action twice a term. “Some aspects of the tradition of the school need to change,” she says briskly. “There was a culture of teachers not being used to someone coming into the classroom and monitoring what they were doing. But it’s something they’ve got to get used to because it’s going to happen more and more. I’ve had nervousness, not resistance.” Meetings are more tightly run now, and minuted. And assemblies have been reorganised. National test results are already good, with about 80 per cent achieving level 4 at key stage 2 last year.

In between scaling the educational heights in Lincolnshire, Kirstyn Doherty has also found time to get married, to a policeman. Her future plans - “God willing” - include a family of her own, and she doesn’t see herself, she says, doing the same job in 10 years’ time. “I’d like to move into one of three areas - teacher training, advisory work or becoming a voice for education in some way.” Any words of advice for other ambitious young teachers? “Go for it,” she says. “In this day and age, if they feel they’ve got the skills to be able to be a head, age should not be a hindrance.”