Peggy So Sin-lee, his school social worker, says Willie did not mean to make trouble. "He couldn't control his impulses. His parents thought he was just being naughty and boisterous, and did not seek medical help. We arranged for him to visit a private psychiatrist, who made the diagnosis.

"His case was later referred to government psychiatrists, but he only got to see them once every few months, and his condition did not improve at all."

Thousands of Hong Kong students have experiences similar to Willie's.

Dr Kenneth Sin Kuen-fung, an associate professor at the Hong Kong Institute of Education, says more than 80 per cent of the city's 1,000 mainstream schools now include special needs students.

For every special needs pupil enrolled, schools receive between HK$10,000 and HK$20,000 in addition to annual funding to employ more staff, or pay for specialist services.

"Schools use the extra funding in different ways, with some employing outside speech or occupational therapy services for special needs students. But not all students need the same type of services. Many parents complain their children do not benefit at all, even though each of them is entitled to the extra funding.

"The government made it compulsory for schools to enrol teachers for on-the-job special needs training. But just 20 to 30 per cent of the [50,000] teachers have completed this training so far. Besides, the 30-hour programme hardly equips them to deal with the different kinds of special needs students," says Sin.

Intensive therapy from an early age can work wonders (see box) but few parents can afford frequent private sessions.

The inadequacy of special needs services starts in preschool. Social Welfare Department figures show more than 6,700 children competed last year for 6,230 places on its remedial programme, which is free to youngsters up to age six.

"The period up to six years old is considered the golden time to help special needs children catch up with their peers. Those who miss this window will be handicapped," Sin says.

So argues that with its inclusive policy, the government should make special-needs education part of undergraduate teacher training instead of the current piecemeal approach. Teachers won't be able to devote sufficient attention to special needs students in an integrated class. But the school can gather them for support sessions for help from specially trained teachers.

"The government should also set rules on how the special needs subsidy is used. Now, some schools just use the money to employ more teaching assistants, who have no special needs training and are just assigned to lessen teachers' workload."

Many wind up like Willie Lam, muddling through their school years and unsure about what to do with their future. To fill the gap for special needs assistance in schools, the Hong Kong Family Welfare Society launched a career-counselling programme last year for senior secondary students.

The series of weekly workshops, designed to identify their areas of interest as well as strengths and weaknesses, are complemented by industry visits. Jacqueline Ng Wai-ling, the society's senior manager in youth services, says the aim is to help special needs teens set their life goals.

It has been a revelation for Willie, one of 60 students who have completed the programme so far. Inspired by what he learned about graphic design, he is studying for a diploma in information technology at the Vocational Training Council.

"I like making computer graphics. After talking with the career counsellor, I decided not to go on to Form Four; all those academic lessons don't interest me anyway. I enjoy studying for the diploma," Willie says.

"After I joined the programme, I began to think about my future career. I never thought about it in the past, as no one at school told me anything about jobs."

The transition to adult life is no easier for autistic teens attending special schools. Few are able to keep a stable job after leaving school, even high-functioning autistics, says Christina Chan Ying-ha, of the Heep Hong Society's Jockey Club Parents Resource Centre.

"I have been working at the centre for over 10 years we have never had anyone earn a university degree. Of all my charges, there are not many who can get a job. Many work in sheltered workshops and others continue to receive training so that their ability to look after themselves will not deteriorate," Chan says.

Some obvious traits prevent them from holding a job for long, she says.

"Autistic people tend to have poor social skills. They often mumble to themselves and speak in a loud voice. Not many employers are patient and understanding enough to accommodate such differences."

Chan says training can help them better cope with life as adults. "Social training is crucial. The biological and mental changes that come with adolescence can be a shock. They begin to develop an interest in the opposite sex, but don't know how to deal with it. We need to help them better handle the transition to adulthood. I have seen some get married and have a family, but they are in the minority."

That's why the future is a constant worry for Wan Yan-tai, whose 24-year-old son Wong Ying-ki is autistic.

Although considered high-functioning, she says, "he doesn't know how to talk to people. He keeps talking about his favourite cartoon characters and people think he's a child.

"I am worried that he won't be able to set up a family, although he can take care of himself now. He's always eager to help people. If a person asks for directions on the street, he will go out of his way to take the person where they want to go. But I am worried that he might run into criminals."

Wong showed telltale signs of autism as a toddler - he was obsessed with moving things like wheels and he suffered speech delays.

Despite being diagnosed at age two, Wan says, there was little assistance available for her son's condition. "As a preschooler, he received speech and vocational therapy only every one or two months because places were limited and there was a long queue. I enrolled him in training classes offered by NGOs like Caritas."

He later attended a mainstream primary school, which did not provide any help, so Wan enrolled him in Heep Hong for remedial programmes.

Her son went on to Fortress Hill Methodist Secondary School, which catered to children with severe learning difficulties, but even there the reception could sometimes be unsympathetic.

"His [Form One] teacher scolded him for looking at the fan all the time. He didn't understand why he was different from the others," Wan recalls. That's when she told him about his condition.

"As he grows older, what most worries me is his failure to understand the complexities of life. He's innocent like a child," she says.

Happily, her son seems to be adapting. A hotel internship that was part of a vocational training course run by the Hong Chi Association has led to a job as housekeeper.

"It took half a year for him to relax," says Wan, recalling how his clothes were drenched with sweat when he returned from work because he was so nervous.

"Now he talks to me about his work all the time. I never get complaints from his boss and colleagues. I am glad that he loves his job."