"Oh, I'm sorry, I thought you were the father of one of my children," must be the oldest gag in the teachers' joke book. But the joke was on me the other day when I saw a middle-aged man who did look like the father of one of the children I had taught. Looking closely, I realised it was the child himself; he was 10 in my class 25 years ago. He has Down's syndrome.
At one time, people with Down's had a very reduced life expectancy; these days it's not uncommon to see them in their sixties or seventies. I was talking to such a man recently who had just lost his mother. It's a big worry for parents who have disabled children. How will their kids cope without them?
At my special school, we put great emphasis on independence and applying key skills to real-life situations - catching a bus, shopping, cooking. Of course, not all our pupils will be able to do this and some may be dependent on other people all their lives. But it's with a real sense of achievement that we see youngsters leave school with the skills they need for independent living and, just as importantly, with a positive attitude to life, an ability to get on with others and good self-esteem.
The other side of this coin is that, having spent many years in such an accepting and encouraging environment, they and their families can find it a shock when they leave. We do what we can to ease the transition and increasingly give the youngsters experience of the outside world - at college, in mainstream schools and in the community generally.
We usually have nothing but positive encounters these days, although, in the past, people would be uncomfortable, condemnatory and even abusive when they encountered our special children. Nearly as bad were the people who guiltily shoved a fiver into the teacher's hands saying: "Bless them - get them an ice cream or something." I found this insulting. Why were our children in need of money more than any others? No, what our young people need, particularly as they grow into adulthood and lose their "cuteness", is acceptance and a full place in society.
The middle-aged man I spoke to is a dancer and performs in schools and old people's homes. He lives with his friends in a neighbourhood house and enjoys a pint in his local. Good for him.
Maria Corby is deputy head of a special school for pupils with severe and multiple learning difficulties. She writes under a pseudonym