Northland primary school principals say they are seeing growing numbers of violent new entrants and getting less support to deal with them.
Three Whangarei primary school principals have complained about a lack of support for new entrants with serious psychological problems.
Another principal in Northland says research is urgently needed on the growing numbers of violent and unmanageable children entering the school system.
Principals said they are having to beg for specialist help and teacher aides while the Government spends $60 million on a behavioural management programme for teachers.
Tai Tokerau Principals' Association vice-president Marilyn Dunn said there has been an influx of new entrants to Northland schools raised in homes where they have seen violence, methamphetamine and alcohol abuse since they were born.
Ms Dunn said such children are often aggressive and need the help of a teacher aide for prolonged periods to keep them and others safe.
She said the Government's new Positive Behaviour for Learning programme for teachers does not provide for this and schools need far more specialised help.
But the Ministry of Education on Monday defended the level of support available to schools dealing with violent or disturbed children.
The ministry said its special education teams are working with between 3000 and 4000 pupils throughout New Zealand who exhibit particularly challenging behaviour. It said the teacher aide budget in Northland is unchanged.
However principals say in practice, that amounts to a funding cut - because they are dealing with growing numbers of damaged children and there is now less funding to go around.
Prime Minister John Key said he does not know whether there has been an increase in violent cases in Whangarei, but the Government has been rolling out more and different resources including more social workers in schools.