High schools are not prepared for a "tsunami" of children with autism who need greater education options, an autism support group has warned.

Key points: A large number of children with autism due to start high school

A large number of children with autism due to start high school Autism Awareness Australia warns high schools not equipped for the influx

Autism Awareness Australia warns high schools not equipped for the influx Parents in the Hunter Valley have organised to build a school their own children

"We've seen this coming," Nicole Rogerson of Autism Awareness Australia told 7.30.

"We know that this is a tsunami level of kids about to hit high school, and we're not prepared for it in any state in Australia."

She said there need to be more specialist schools at high school level, as well as more high schools with teachers trained to work with children with autism.

"Ideally, we would like every child with autism to be educated in their local school, but for some families that is not possible," Ms Rogerson said.

"We do need these specialist units, and we need to be real about how many kids we need to place in those and start planning accordingly."

Support for children to 'learn at their best'

Aspect Hunter School principal Lara Cheney said each young person's individual needs are assessed. ( ABC News )

Worried parents in the Hunter Valley, north of Sydney, have already decided to take matters into their own hands.

With no specialist high school in the area for children with autism, they decided to rally the community and build their own school.

Local businesses helped out with free materials and labour, and dozens of parents volunteered to help.

"We've had a painter turn up on his own that lives locally and offers to paint a few classrooms," the unofficial project manager, Hilton Grugeon, told 7.30.

"We had other businesses that send their workers here and don't put in a bill for it."

The result is Aspect Hunter High School, and it took in its first pupils this year.

It is run by Autism Spectrum Australia (Aspect), Australia's largest non-profit autism service provider, and started with 13 pupils but has capacity for 60.

"The criteria for enrolments is a diagnosis of autism," the school's principal Lara Cheney told 7.30.

"We have children across the spectrum, and all our students have such individualised needs and strengths and interests."

That level of attention is labour intensive, with four staff members employed for the 13 students currently enrolled.

"We do have that higher staff-to-student ratio, which is really important in being able to achieve the outcomes that we do," Ms Cheney said.

"We are delivering the mainstream school curriculum.

"It's always working out each young person's individual needs and then how to support them to learn at their best so they reach their fullest potential."

'There's no bullying and good friendship'

Callum (right) with classmates and a teacher's aide ( ABC News: Jerry Rickard )

Toni Janaly's 13-year-old son Callum was bullied and left out at the mainstream school he had attended.

"I've moved from worrying about his future to being excited about his future," she told 7.30.

"We all understand each other in our class," Callum said.

"And there's no bullying and good friendship."

When students were asked how they feel about their new school, the replies were all positive.

"Paradise", "awesome" and "perfect" were among the responses.

That's a stark contrast to how these students with autism felt at their previous schools, where their experiences included being bullied and expelled.

"I don't get pushed, [I'm not] being called names or being bullied," new student Lachlan said.

Why did he think that had been happening previously?

"'Cos I'm different."

'The teachers called me a monster'

Brittnie Gillmore and her mother Toni are relieved to be at the new school. ( ABC News: Jerry Rickard )

Brittnie Gillmore, 15, went to a specialist school during her primary years, but once she reached high school age she went into a regular school.

"I got bullied a lot," she told 7.30.

And she didn't just have problems with other students.

"The teachers called me a monster and said I was too dangerous to be around," she said.

Her mother, Toni, said: "She wasn't able to regulate her emotions, and she would sometimes become physically violent towards teachers, of course, resulting in a suspension."

In the end Toni felt she had no option but to homeschool her daughter, so being accepted into the new school was a welcome alternative.

"It's such a relief for Brittnie and to see her happy and to feel included and accepted," she said.

"Her meltdowns have definitely decreased because she is so happy. She doesn't come home full of anxiety."

We want a 'truly inclusive education environment'

Nicole Rogerson says State government's should have planned for more students with autism. ( Supplied: Nicole Rogerson )

Ms Rogerson said the concerns of the parents in the Hunter Valley are common across Australia.

"My preference, absolutely, would be to have better services in local schools so that all kids can be educated in their local community and we have a truly inclusive education environment," she said.

"That's what we really want.

"But I do understand for some families, for some kids, that's just not as easy as it sounds."

7.30 contacted each state's Education Department and NSW, Queensland, South Australia, Western Australia and the Northern Territory all acknowledged increases in the number of students with autism.

Ms Rogerson said it was beyond time for state governments to act.

"Sheer enrolment numbers show how many children at the kinder and primary level on the autism spectrum were enrolled, then add up the years and look at how many we are going to have in high schools," she said.

"The fact that we don't have those placements should be a shock to nobody.

"We do need these specialist units, specialist educators and we need to be real about how many kids we need to place in those, and start planning accordingly."