A group representing more than 2,300 school principals has begun a public campaign against the national standards in reading, writing and maths.
The Principals' Federation wanted the government to halt implementation of the standards and review them.
That has not happened and on Tuesday it began a campaign against the standards which includes a website with a video of principals explaining their opposition.
The federation says the vast majority of principals feel the standards are morally wrong and will cause significant damage to children and schools.
Its national president Ernie Buutveld told Checkpoint the campaign is an effort to make parents aware of problems with the standards.
"Under tomorrow's schools we have a system that talks about partnerships with communities and with schools, in fact schools belong to those communities.
"If we want to honour that partnership then it behoves the Government to listen to those people," he said.
The Minister of Education, Anne Tolley, says the federation's campaign is political and is aimed at confusing and upsetting parents.
And she says some principals have told her they are taken aback by the federation's decision not to join the advisory group.
Ms Tolley invited the federation and other education groups to take part in a national standards advisory group.
But the Principals' Federation says it will only be looking at implementation issues, and will not make the fundamental review it says is needed.
Primary school principals' opposition to the national standards has been growing for months. Earlier this year, their federation agreed the standards are flawed and need to be redesigned.