They call them the "Velcro children". It is the name teachers at Cedar Hall use for pupils who find it difficult to cope when they move to the special school from mainstream education.
Peter Whelan, headteacher, said: "We call them the Velcro children because they are used to being attached to a learning assistant for every hour of the school day.
"When they come here they sometimes find it difficult to mix and work on their own - one of the children I spoke to would only say 'You do it. You do it'."
Staff at the Essex school, which caters for pupils with moderate learning difficulties, believe the children's problems illustrate how "inclusion" in mainstream schools can have the opposite effect.
Instead of feeling included by their peer group, the pupils can be cordoned off from other children - in some cases literally by physical barriers in the classroom.
Maria Hutchings, a Cedar Hall parent, highlighted the problem this week when she appeared at a press conference arranged by the Conservative party.
She claimed, wrongly, that the school was threatened with closure.
A tearful Mrs Hutchings also said she had been horrified by the treatment of children with special needs in mainstream schools when she had been searching for a place for her son, John Paul.
"I went to a mainstream school to see an autistic child benefiting from inclusion," she said. "I found a child behind a four-foot white screen with an assistant for 20 hours a week - an assistant with no specialised training or education, who happened to answer an ad in the local press."
Mrs Hutchings, who heckled the Prime Minister during a live television debate, said she had faced a "nightmare of bureaucracy and lies" to get John Paul into Cedar Hall.
Essex council had recommended her autistic son attend a mainstream school, but the public relations worker got her way after threatening to take her story to the local press.
The Conservatives used Mrs Hutchings's case to promote its plans to give parents the "Right to Choose" special schools as well as mainstream education.
They promised to block closures of special schools and to set up a Research Institute for Special Educational Needs, costing around pound;10 million a year, which would advise schools and develop a new system for assessing children's needs.
Despite their claims about parental choice, however, the Conservatives'
policies could give more power to headteachers than families.
A spokesman for the party said: "Our policy is that the parent would be able to choose the school, but it would be up to the head to make the final decision."
The Conservatives' publicity stunt was also undermined by the fact Mrs Hutchings's local authority is Tory-run.
Mr Whelan was not embarrassed, however, to see a Cedar Hall parent haranguing the Prime Minister. "It was a surprise," Mr Whelan said. "But I'm now thinking about persuading her to become a parent-governor."