The Government has launched a last-minute publicity campaign to educate parents about the new national standards, saying people are confused about the changes.
From Tuesday, students in primary and intermediate schools will be assessed against national standards for numeracy and literacy.
Prime Minister John Key has announced a $200,000 mailout to 350,000 homes about national standards and says an expert committee will be set up to advise on any problems that occur during its implementation.
National MPs will also be sent around the country to hold public meetings on the issue.
Critics of the policy have called for trials in a limited number of schools before it is implemented nationwide.
Mr Key says some unions, principals and teachers are resistant to change but will have to get used to the idea that national standards are now a legal obligation.
He says there has been a lot of misinformation about the policy.
"Just because there's some resistance to a policy from a union, doesn't mean it's not a successful policy. I'll tell you what's not going well - 150,000 kids leaving school with hopelessly inadequate literacy and numeracy skills."
The Labour Party says Education Minister Anne Tolley is not up to the job and should have been sacked over her handling of the national standards issue.
Labour leader Phil Goff says the Government's publicity campaign shows the implementation of the national standards is a shambles and Mrs Tolley has failed to get school principals on board.
Government accused of double standard
The Principals' Federation says the Government is guilty of a double standard in its introduction of national standards in schools.
Federation president Ernie Buutveld says Maori schools are not being compelled to accept the new system.
He says kura kaupapa, which are state schools, are concerned about the effects of national standards.
However, he says unlike schools that teach in English, kura kaupapa are being consulted at length about the system and allowed to trial it first.
Mr Buutveld says that is what mainstream schools have been asking for and it is unfair to deny them the consideration being given to kura kaupapa.
The primary teachers union, the NZEI, is launching a petition calling for a trial of the national standards, saying they are just another costly, untested assessment system that will not help underachieving children.
The union also embarked on a national bus tour campaign on Tuesday to meet with communities.