The department's reasoning: the best place for Isabelle is in a school environment.

But, her parents argue, Isabelle already goes to school so she can mix with other children. She doesn't learn there. As an autistic child, her education depends on one-to-one tuition by a trained professional. Now that this has been taken away, she is regressing rapidly.

"Isabelle used to take a step forward every week, " says her father, Pat Gavin.

"She could interact with others and you could hold a conversation with her. Now that has all changed. She is agitated and bored, more difficult to deal with. She isn't even interacting with her sister like she used to."

Gavin is just one of 90 parents around the country whose children's home tuition was withdrawn by the department earlier this year.

The only reason the parents have been given is that the government believes an autistic child is better off in mainstream education.

"I would agree, once the proper supports are in place, but they're not, " Gavin told the Sunday Tribune. "When Isabelle started school, there was an autistic team in place with a psychologist, psychiatrist and speech therapist.

Within six months they had all left the department and the school was left to cope on their own.

"They do their best for Isabelle and give her five hours of tuition a week, but it's tough on them and not fair on the other children."

All around the country, parents of autistic children are struggling to get them an education. Last week there were two cases in the High Court taken by parents suing the Department of Education for not providing for their children. Such cases are ordinary occurrences.

In several areas, parents have set up their own school for their children, under a system known as Applied Behavioural Analysis (ABA).

Based on behavioural principles and evidence-based research, it is designed to engage students actively in the process of learning and has a good success rate.

These schools are battling for funding, however, and many are still struggling to get off the ground.

Waterford Applied Behavioural Analysis School is one such school. Five years ago, a group of parents came together to give their children an ABA education. One year ago, after extensive lobbying, they got approval from the Department of Education. As of now, they are still waiting for funding to be released to the board of management and the school is unlikely to open in September. Twelve children are waiting to start and 43 are on the waiting list.

"This has just been dragging on and on for years, " said Lucy Phelan, patron of the school and mother of two autistic boys. "The way things are going now, this school is not going to open in September, but it has to.

Time is going by and our children are getting older. They need this education now if we're going to see the results."

Two of Phelan's three sons are autistic. Johnny, 10, is what she calls a "classic autistic" and doesn't talk.

Matthew, eight, is the other extreme and talks "all day long". Both have very different needs.

"When you have two autistic children, you have quite an investment in the school system, " said Phelan, who is halfway through a degree in psychology. "There is nothing that will suit both of them, and that's where ABA comes in. It is all about finding an individual path of learning. If one doesn't like doing something that way, they'll find another way.

You can see the science, and that is a real comfort to parents."

Johnny and Matthew have been taught at home by Phelan's sisters, Amy and Michelle Byrne, since she took them out of school five years ago. Phelan grew up with an autistic brother and watched her mother struggle to get him an education. The same won't happen to her, she said.

"If Johnny had had ABA at age two-and-a-half, he'd be talking now, " she said. "I'm not here for a cure and I know my children are as good as they can be, but I have to think of the future. People will always be compassionate to an autistic child, but when they're adult, it's a different story. I want them to have a chance at independence and we need the school now if they're to get that."

Early detection and education are essential for the treatment of autism. Under the current system in Ireland, parents are forced to wait up to two years to have their child diagnosed.

"The whole situation is a ticking time-bomb, " said Kevin Whelan of Autism Action Ireland, which recently set up the National Diagnostic and Assessment Centre to get children diagnosed more quickly.

"The state says the best strategy is to include children in mainstream education, but that's like the Tanaiste saying all old people should be in nursing homes.

"Different approaches are needed to cover all cases. The state needs to put the money into education because otherwise they are going to be paying for the care of autistic adults all over the country, " he said.

"I'm at the end of my tether but I'm not giving up, " said Gavin, a member of the Voices for Autism group in Co Clare.

"My child deserves an education."

Phelan agrees. "It is a wonderfully exciting life, to have autistic children . . . a chance to travel the path less travelled, " she said. "I'm not normally emotional, but when I visited an ABA school last year and saw how the children were doing, I wanted it so bad for my boys that it was like a pain.

This is what they need to become happy adults. That's what all us parents want: for our children to grow into happy adults."