Primary school teachers and principals have rejected a pay offer from the Government and have voted to strike.
It was announced on Tuesday that members of the New Zealand Educational Institute (NZEI) voted "overwhelmingly in favour" of stopping work for half a day on August 15.
- 'Patient' teachers ready to fight for better pay
- National blames Government for industry strike action
They are now discussing whether to extend it to a full-day strike, as some members don't think striking from 1:30pm to 4:30pm would send a strong enough message, according to NZEI lead negotiator Liam Rutherford.
They were offered a pay rise over three years from the Ministry of Education, but votes taken at paid union meetings in June showed the majority have opted to reject it.
The offered pay rise ranged from a 6.1 percent increase for the top of the pay scale, which would have made the maximum teacher's salary about $80,600, to a 14.7 percent increase to the entry salary, bringing that to $55,030.
NZEI says 86 percent of teachers have been offered a pay increase of just 2.2 to 2.6 percent a year for three years.
The teachers' union originally asked for a 16 percent pay rise over two years in an attempt to solve New Zealand's teacher shortage.
Members also asked for more time to teach and for additional support for students with special learning needs.
Under the Ministry of Education's offer teachers would be given just 12 additional minutes per week to work individually with children or to plan and mark work, according to NZEI.
It also says the union's request for funding for a Special Needs Coordinator (SENCO) in every school was ignored by the Ministry.
NZEI will continue negotiations with the Ministry in the coming weeks to try to reach a settlement.
Louise Green, NZEI lead negotiator for principals, says school staff are very conscious of how a strike may inconvenience students and their families.
"We're taking action now to avert the very real threat of larger class sizes within just a few years."