Education groups will join forces next week in a bid to overturn the Government's revised class student-teacher ratio funding formula.
Teacher unions have taken heart at the rebellion against the funding cuts by parents and traditionally moderate groups.
The principals of the Association of Intermediate and Middle Schooling (NZAIMS) yesterday called on schools to withdraw their support for the Ministry of Education changes and refuse to join a working party to implement them.
President Gary Sweeney called it more "civil disobedience" than industrial action. But he said that in his 20 years as a principal, he had not seen such a response to change.
"We cannot continue working with a Government ministry that cannot work in a fair, transparent and honest way with us," he said.
"There is genuine anger from a lot of very senior principals in the system."
Organisations representing teachers, principals and trustees will meet in Wellington on Tuesday to plan action against the cuts.
As well as NZAIMS, the meeting will include the Secondary Principals' Association, the Principals' Federation and the School Trustees Association. Also represented will be the teacher unions: the Educational Institute (primary) and the Post Primary Teachers' Association (secondary).
Education Minister Hekia Parata faced a large and rowdy demonstration by parents, teachers and children while giving a breakfast speech in her Wellington electorate of Mana.
And pupils in some schools are being urged to lobby Government MPs.
Ms Parata has already softened the extent of her changes to student-teacher ratios.
On Tuesday, she assured 245 schools - mainly intermediates which could have lost between two and seven full-time positions - that none of them would lose more than two positions over three years.
Asked in Parliament yesterday what would happen after that, she said the policy would be reviewed over that period.
But that has not quelled the opposition. Mr Sweeney, who is principal of Pukekohe Intermediate, said his association's action was aimed at the Ministry of Education because it was the body schools dealt with daily.
"The ministry has broken a relationship with us. They didn't consult, they just threw a scenario at us, then they threw a solution that they thought was right at us - two teachers instead of four or five - then they throw a working party idea at us.
"We've had enough."
One of the first instances of non-co-operation was refusing to work with Otago University researchers studying learning at Year 4 and Year 8 for the ministry.
He knew of three schools that had told the researchers they would not co-operate.