Becoming a teacher wasn't a life long ambition. I did a degree in psychology and had the option to do a PGCE with a focus on educational psychology. I anticipated doing four or five years in the classroom and then training to be an educational psychologist.

I trained in Leicester but moved back to my hometown of Banbury. I ended up teaching maths at Banbury FE college. I'd done maths and statistics at A-level. The job was fascinating in many ways but I found the atmosphere disappointing. There didn't seem to be any opportunity to learn from colleagues or to get any feedback, I was just left to my own devices.

Then I got a job in south east London at Abbey Wood School. It was a huge, struggling secondary school in one of those parts of London which was built to house the overspill from slum clearance. The PGCE I did was a route to working with what were then called remedial classes. I was mainly working with smaller groups of children who needed extra help. There was no consistency and nothing felt coordinated. In a way you could make everything up and that was what was expected really. The school's ethos was: it doesn't matter what you do with them, just keep them out of trouble. The children were pretty much written off. Many of my colleagues had completely different attitudes and did have aspirations for the pupils but that wasn't the culture of the school. There were some really tremendous teachers there and I learnt a huge amount there from my colleagues. But the school just couldn't shake off its ethos. And that's one of the reasons why it closed and became an academy. I was there for three years and probably the biggest thing I learnt was that this was an area of work which I wasn't really cut out for. I didn't have the maturity to think "this is one school, maybe I should work in another one," instead I thought "teaching isn't for me".

My wife and I decided to move back to Oxford and I went back to working at Banbury College, just treading water really. I thought I'd just get a few more years teaching in a secondary or even primary school before doing my educational psychology training.

Then an opportunity came up at Frank Wise School. I only noticed it because it was just down the road. I wasn't looking for a job in a special school but I thought I'd give it a shot.

At this time the school was small, there were less than 40 students. They were looking to replace four teaching jobs and appointed three people full time. They took a risk by employing me as a temporary teacher because unlike everyone else I hadn't done a four-year special needs qualification.

During my first visit, I fell in love with the school. It had such a buzz. The kids were so interesting. I started off team teaching with an incredibly skilful chap which meant I was now effectively doing my training in school. I was sent on courses including language development. The post was made permanent which was so great. Everything just fitted right from the start.

I'd finally found the whole school ethos that I'd been feeling my way for. I was living and breathing it. It felt exactly right to me. All my thoughts of giving up teaching just disappeared.

The things I thought would be most tedious, that is being with a small number of children and teaching them every subject like in primary school, ended up to be the richest part of the job. You get to know the children in such depth and that draws out the intellectual part of the job. You need to design very specific individual learning paths. There is a fundamental belief in the school that when it doesn't work, teachers need to look for the mistake in their theory. If it's not working you must have exhausted every possible idea before you can think the student has reached a limit on this particular path.

It's a fascinating area of work. People often think you must be very patient to work in special needs as the kids are slow and make so little progress and that it must be very rewarding as the kids are so cute and helpless, as if they are little puppies. But the reality is totally different. You must be patient because you have to constantly re-evaluate your practice, but you're working at such fine levels that the children are making more noticeable progress than those in conventional schools. The rewarding side is much more about the pride in their achievements, they may seem miniscule in a wider context, but they are huge.

I started in 1986, just 15 years after the idea that children with special needs should be educated at all. Until then they were just being catered for medically. People said what's the point of devoting so much time and money to these children? What are they going to contribute? But then think of all the time and money we devote to teaching in conventional education doing trigonometry and other subjects that adults may never touch again. The content isn't the point. It hardly matters for anyone. I think education is much more about skills and self esteem, independence for everyone. Everyone should have an investment in their education and well being.

Our school doesn't label our pupils using medical terms because they are really meaningless in an educational context. Labels don't tell you about the individual. Instead we ask, can they walk or talk? Are they outgoing? Do they like maths? Do they have friends? It's a relief for many parents to get a medical diagnosis but once they come to Frank Wise we have to work on forgetting it, putting it out of their mind. Sometimes parents are told their child will remain unable to communicate. In 25 years, I've never met a child who can't communicate in some way. It could be a reaction to something they've tasted. That's a starting point, we'll work with them. Sometimes a child's condition will start to deteriorate but we don't give up. It's like giving up holidays if you can't get to Greece or Australia any more – there are other holidays just as exciting that are a little more accessible, more achievable.

The school has grown. We now have have 106 pupils and 90 staff. As the school grew I was drawn into management work and became deputy head at the turn of the millennium. I didn't become head until 2007. I didn't apply for the job and didn't want it at first. I wanted to maintain the little classroom teaching I had (I did two days a week) as a deputy and thought my workload was already huge. The previous head Kevin Griffiths had been there for 25 years. He did a phenomenal job taking the school from a child-minding service to a powerful force with incredibly good staff and educational ethos. We'd just got an outstanding Ofsted.

My thoughts were: if I become head I won't be perceived as competent as Kevin, we'll be dropped a grade on Ofsted, the wages aren't much more. It wasn't terribly appealing. We couldn't recruit the right head so I said I would be acting headteacher for one year. But over the preceding summer, I started planning what I'd need to do, and over that period I thought possibly the person I wanted to recruit was me.

I decided to give it a term and see. I found I loved the role. I've been incredibly lucky that these opportunities have come up and I feel great pride in the school. One of our core values is developing people's understanding of special needs particularly through technology. We've been able to sell our point of view which is that the best way you can approach individual education is to work with children as individuals and not be restrained by what you'd expect by the label. Sadly, label-led education continues to be the way for many schools and there's a real risk with label-driven funding.

Sean O'Sullivan is head of Frank Wise School. Read Sean's blog. Frank Wise is a Net Advocacy School for the National Education Trust. One of the few special schools involved.

Thank you to Sean O'Sullivan for sharing Frank Wise's progressive curriculum. He is keen to point that this is just a snapshot that will continue to evolve and develop over time.

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