A strongly-worded letter has been sent to school boards reiterating that it's their responsibility to enforce compliance with the new national standards.
The letter from School Trustees Association president Lorraine Kerr, was not sent to school principals.
Ms Kerr says the organisation has received several queries from boards regarding their rights if principals and teachers indicate their opposition to the national standards.
She says boards are accountable for ensuring the new teaching standards are followed and if principals refuse, boards should direct them to comply. If that directive is not followed the problem becomes an industrial issue.
Ms Kerr says principals ultimately have to comply with any lawful instruction, or face the consequences.
Ms Kerr denies using bullying tactics. She told Morning Report the letter was in response to boards asking for guidance on how to deal with principals who are effectively campaigning against national standards.
Ms Kerr said 18 boards have indicated their concern that their schools may not comply with the standards.
She said it simply sets out the consequences if schools break the law.
However, the New Zealand Educational Institute says the letter only serves to inflame the situation and is bullying boards into making principals and teachers comply.
Public meeting with minister
Meanwhile, Education Minister Anne Tolley has told a meeting in Tauranga that while national standards are here to stay, feedback from teachers may lead to changes.
While she said there is no chance the framework will be treated as a trial, it is a work in progress - and she suggested public criticism has been based on misinterpretations.
The meeting - attended by about 30 people - was the latest in a planned series of presentations by MPs.
Mrs Tolley said parents can expect two written reports this year on their child's progress.