Primary teachers and principals have voted for full day strike action on 15 August.
The teachers’ union NZEI has been seeking an immediate 16 percent pay rise and improved working conditions since pay talks with the Ministry of Education began in May.
Lead negotiator Louise Green said the decision to strike on 15 August sent a strong message to the government that it was time to fix the crisis in teaching.
Ms Green said it would be up to boards of trustees to decide whether to open schools during the strike.
“We know this is an inconvenience for parents, but we also know that our parents want the best education for their children,” she said.
The last time teaches took strike action was 24 years ago.
NZEI and the Ministry of Education agreed yesterday to enter mediation over collective agreement negotiations.
Education Minister Chris Hipkins said he hoped mediation would prevent the full-day strike.