Twenty five years ago, a disability meant a bar from teaching. Only those who passed a stringent medical were deemed fit to be in the classroom. Even today the National Bureau for Students with Disabilities estimates that only one teacher in 1,000 is disabled.
"There are barriers all the way down the line," says Richard Reiser of Disability Equality in Education. "Having a disability can make it difficult to find a school for teaching practice. And once you've qualified, headteachers and governors are often wary of what they see as extra hassle."
But there are six million disabled adults in the UK, and the Disability Discrimination Act (1995) means teaching should be open to anyone. So what's it like being a teacher if you are disabled? Not easy. But those already in the job say the personal rewards make the extra professional demands worthwhile, as the following examples show.
When Mabel Davis went deaf at the age of seven following a bout of TB meningitis, her mother noticed a change in her personality. No longer quiet and private, she became more assertive, making sure she was included in conversations and activities. Now, as the experienced head of Heathlands school for the deaf in St Albans, Hertfordshire, she admits some people might call her bloody-minded. "I refuse to be beaten by a system that cannot look beyond the disability. But it's not about conflict or confrontation. I like to think it's about humour and winning people over."
Ms Davis has been teaching for 24 years and is just starting her 12th year as head at Heathlands. During that time she has engineered a unique inclusive partnership with the local mainstream comprehensive, Townsend, where Heathlands pupils are taught all their practical and visual subjects.
She has won the Royal Association for Disability and Rehabilitation's Person of the Year award (1993), and become a founder member of the General Teaching Council, where she fights for disability rights. She is still the only deaf headteacher in the UK.
In many ways she regrets the move into management. "My heart's in the classroom," she says. "When the children emerge as independent young people with a positive self-image, willing and able to make a full contribution to society, all my hard work has been worthwhile. I burst with pride for them."
Although Ms Davis has achieved so much in teaching, her early career was a hit-and-miss affair. "I found my metier by accident," she says. When she offered to help with the library at a school for the deaf in Liverpool, she was thrown instead straight into teaching in the FE department, and realised she needed some training. "So it sort of took off from there. I never thought of being a teacher, never mind a headteacher," she admits. "I still hanker after being an investigative journalist, but being deaf isn't the best qualification for that."
Although she was offered a job in a mainstream school, Ms Davis believes her skills are more helpful to deaf children. "Language development depends on a fluent dialogue between teacher and child. Deaf children can identify with me. We build up a great rapport communicating in sign language."
Parents, too, she finds, are reassured by meeting her. "They see that deafness is not the tragedy they thought it was."
Ms Davis speaks well, uses a sign language interpreter at meetings and a palantypist (a speech-to-text specialist who uses a special keyboard to record conversation phonetically) when the discussion is quicker and more complicated. Yet she still believes her deafness has been "a real brake on progress. It's restricted me in a big way." At first, for example, she had to win the support of her fellow heads, some of whom were "a bit wary". And she sometimes regrets having to be so forthright. "I have to be so obvious if I want to participate in conversations or at meetings. Given the choice, I would prefer to remain quietly listening until I choose to come forward.
It's robbed me of my privacy."
One place she is ensured privacy is at her holiday home, a converted coachhouse in her native Scotland, where she writes and makes abstract sculpture. One of her larger pieces is to be used in a calendar for 2004 showing the work of deaf artists. Along with her grandchildren, who are "the light of my life", her sculpture is important to Ms Davis. "It's a wonderful hobby. It reduces the pressure on me and stops me bopping someone on the nose when things get fraught, as they often do."
John Holroyd was born blind in one eye and partially sighted in the other.
In 1997 a cataract growth threatened his remaining eyesight. It was a time when he was thinking of moving up the teaching ladder into management.
Instead he was faced with a battle to keep up with his current job. "It took six months to diagnose the problem. I kept thinking, 'I'm going to lose my job'. Everything became so tough."
Mr Holroyd is head of an expanding RE department at independent St Dunstan's college in the south London borough of Lewisham, where he has taught since 1991 after five years in inner-London comprehensives. His cataract has been removed but the experience made him reflect on his long-term career. "I was always competitive. After the cataract scare I realised my job wasn't everything. I've tried to set my own goals rather than always comparing myself to other people. And I've come to terms with the likelihood that I'll stay at this level of teaching."
Mr Holroyd has no problems in the classroom. He enjoys teaching, but it's the "paper shuffling" he finds increasingly difficult. He reads slowly, even with the help of equipment to enlarge text, and often relies on support staff to read to him so he can dictate comments and marks. Mr Holroyd gets funding for these through the Access to Work scheme, run by the Government's employment service, but finds reliable people difficult to recruit. "Just when I get someone good, they move on. And it's a personal relationship. Sometimes it works and sometimes it doesn't."
He finds inflexible deadlines particularly frustrating. "It takes me longer anyway to go through coursework, for example, because of my disability.
There have been times when I've had to work 80 hours a week or more."
Mr Holroyd recognises that his needs have increased over the years. He finds it difficult to write now and has back problems from bending over to read. But St Dunstan's remains "very supportive". He has just become the school's induction tutor for NQTs, and his headteacher, Ian Davies, describes him as "one of my best heads of department". And while Mr Holroyd would like to see more support for disabled teachers, he finds it difficult to know exactly what could be done. "People's needs are so diverse.
Everything I use has to be tailor-made for me. It's hard to know what could be introduced that could make a real difference to many people."
As an RE teacher, he has found his subject important in his determined effort to get the most from his job. Not because of any strong religious beliefs, but because it allows him to "be an explorer". He attends Quaker meetings and Buddhist retreats and regularly travels to religious sites in Vietnam, India and Cambodia. With his own professional ambitions on hold, it's cultural exploration that drives him on. "I have a passion for thoughts, ideas and lifestyles. I want to be able to give children the opportunity to find their own spiritual beliefs."
He exudes a certain Zen calm when he talks about himself. "I've learned to find a balance, to take up challenges but not to overreach. You have to find what's right for you as a person."
In 1990, Sheila Dearns, teacher of German and head of Year 9 at the Anglo-European school in Ingatestone, Essex, was diagnosed with multiple sclerosis and since 1993 has had to use a wheelchair to get around school.
For someone who admits to having been a "natural pacer" in the classroom, the imposed immobility might have meant a whole new teaching style. But armed with an adjustable chair that allows her to "see what's going on under the desks", Ms Dearns has made few changes.
"The children aren't bothered by my disability. It's simply not an issue," she says. "It hasn't made them treat me as anything less than I was before.
You should see me in front of assembly - they know when to shut up."
But parents are not always so understanding. "In the past, when I met parents for the first time, I'd see a look of shock. Then they'd ask me if I'd had a skiing accident. Now I just tell them it's permanent."
Because Ms Dearns's MS developed gradually, her colleagues had more time than parents to get accustomed to her disability. They have been "without exception" supportive, she says. The school has also been able to make alterations to the typically inaccessible 1960s building, giving her an office close to her classroom, and adjusting her timetable to take account of the debilitating fatigue she suffers. But it wasn't just the school that underwent a learning process. "There was a certain amount of damage," she laughs, "getting the hang of the wheelchair. If you twitch the joystick in the wrong direction... Well, I haven't killed anyone yet, although I have run over a few toes."
As Ms Dearns gets older - she is 48 - she finds everyday activities increasingly difficult. "I used to take time off," she says, "but then I'd get bored and depressed. So now I always come in and just do what I can. I teach in a more restrained way than I used to. I talk less."
She concedes that if she'd had to cope with the demands of a family she would have had to give up teaching. "There wouldn't have been enough energy to go round." Now, at home with her two cats, she allows herself a brief nap when she gets home from school before moving into the garden. "I've developed a brilliant form of gardening. There's little I can do myself; even bending down to pull out a weed would exhaust me. So an ex-pupil does the digging, friends do the planting and I just watch."
There are, of course, inevitable frustrations. Ms Dearns admits to "bad moments" when she would love to go for a walk. But rather than forcing her to plan her retirement, these are the times when she most cherishes teaching. "It's kept me sane. Sometimes I come into school feeling appalling. Then I get into a class and I almost leech the energy from them.
There's no way I could give it up. Being head of year means so much to me.
If I get any cards I put them straight on my walls, and if it's a bad day, I see them and think, 'Well, it's not that bad'."
It's the small things that keep Ms Dearns going - seeing a former pupil going to study German at Oxford, offering to race another wheelchair user from the sixth form (she is, she says, sure to win), and meeting up with friends in Germany. "I want to be an ordinary person doing an ordinary job in an ordinary way," she says. "I just happen to be in a wheelchair."
Disability Equality in Education: www.diseed.org.uk