whickerman, it is not as simple as that.
My son has a slight disability, called dyspraxia. It is in the autistic area. Many other children have "problems" like this that come out in disabilities called Aspurgers syndrome and so on.
These children have all sorts of learning difficulties (my son is very bright but cannot read or write very well). Many children with Autism have trouble coping with crowds, or noise, or dealing with other children.
Where I live provides schools for severely disabled children, and mainstream schools for "normal" children.
But what about the children in between, not disabled enough to go to a servely disabled school, but not really "normal" enough to go to a mainstream school.
Most children with Autism go to mainstream school, and schools are given money to provide extra support for them, but often choose to spend it elsewhere, so the autistic kids are left to fend for themselves.
Because my son was different he was picked on by other kids. He was punched (want to see pictures of the bruises?), his school bag was flushed down the loo or thrown over the wall, he was pushed in mud, or cornered in a room by other kids and threatened.
He was terrified by this and often lashed out to try to get away or stop them doing it. Sometime he was excluded for half a day or a day.
Do you suggest it was all his fault, that he should be permanently excluded?
Do you know what it is like to put your hand up and say you got none out of ten for a written test because the supply teacher had no idea he had a disability, and how the other kids laughed.
Before shooting at the hip try to understand some of the problems some children have at school.