Head teachers are sceptical that extended powers to restrain unruly pupils will make much difference, a survey suggests.
The government's White Paper proposes a more clearly-defined set of rights for teachers in disciplining pupils.
The Association of School and College Leaders asked 100 members about the new powers, which would allow teachers to restrain pupils using reasonable force.
It found only 13 thought this would significantly improve behaviour.
Schools Minister Jacqui Smith is to give further details of the measures on Wednesday.
The majority of those polled - 59 - said the measures would have some impact on behaviour, but 28 said they would have no impact.
One head teacher responded: "All new measures will help, but government diktat will help with behaviour no more than it helps with other issues.
"More support on the ground, greater resources, and some progress on tackling society's problems - now that would make a difference."
Another stated: "Students in general are not very different. However, the very few poorly behaved ones now stand out more and seem to be oblivious to any sanction from school or home."
"The real issue is one of resources. Poor pupil behaviour requires specialist input to resolve it. That means specially trained staff and alternative learning opportunities," said another.
'Ills of society'
The association's general secretary, Dr John Dunford, said the survey reflected the fact that the vast majority of students were well behaved, motivated and eager to learn.
"However we do know that behaviour in society has got worse in recent years. Schools cannot be expected to solve all the ills of society," Dr Dunford said.
"Schools need as many tools as possible to help them deal with poor behaviour and, for that reason, we welcome the extended powers to discipline students," he said.
"The government must be wholly committed to all the White Paper recommendations on behaviour and it must provide schools with the resources needed to implement strategies that will have a long-term, sustained impact on improving behaviour."
At a conference - Pupils Behaving Badly - in London on Wednesday, head teachers will hear from Ms Smith as well as Sir Alan Steer, the head teacher who led a government working group on behaviour in schools.