Thousands of secondary and area school teachers are to strike next week after members of the Post Primary Teachers Association (PPTA) voted in favour of more industrial action.
Union members voted for a one-day strike on Wednesday, 29 March, and further action next term - including a series of one-day strikes in different regions.
The PPTA said it wanted a better collective agreement offer from the Ministry of Education.
"This is a clear signal from our members about how they want this settled, and we want to get back into the classroom - so, this is sending a clear message to the government that we want this sorted," PPTA acting president Chris Abercrombie told RNZ's Midday Report.
"We want conditions and pay that attract teachers and retain teachers in our profession. There's an increasing shortage of secondary teachers that's only going to get worse, and so we want to ensure the future of the secondary education sector."
"I know that our parents are with us because they want teachers in front of their kids" - PPTA acting president Chris Abercrombie
The two sides were holding further talks on Friday. In a statement, the ministry said it was "disappointing that the PPTA would announce they are planning another strike next week as we commence another day of mediation to work towards a settlement.
"Both parties have agreed that good progress has been made in the two days of mediation we have already had since the strike last Thursday. We will continue to bargain in good faith today."
Abercrombie said he was hopeful a resolution could be reached before industrial action was taken.
"We don't want to engage in industrial action. We want a settled environment, we want to get back to the job we love, but we also want to ensure that we have enough teachers in our system. And so, I'm always hopeful we're going to get it... Hope for best, plan for the worst."
Last week about 50,000 teachers walked off the job in support of their call for better pay and resources.
Members of the PPTA and the Educational Institute (NZEI) held rallies across the country in the first ever strike involving kindergarten, primary and secondary school teachers together.
"It's incredibly unfortunate that we have to do this disruption, but I know that our parents are with us because they want teachers in front of their kids. They want their children to have a physics teacher, a PE teacher a math teacher that is suitably qualified, and at the moment there's no guarantee," Abercrombie said.
"And so I know parents are with us, I know it's disruptive… But they are with us because they want teachers in front of their kids."
Following next week's strike, union members would not attend meetings outside school hours from 24 April, the first day of the next school term.
In the second week of next term they would put in place a plan to roster students of different year levels home on various days for four weeks.
In the week beginning 8 May rolling strikes would be held, where teachers would strike on different days in different regions starting at one end of the motu and finishing at the other.
Bargaining between the ministry and NZEI, the union representing primary teachers, will take place on Wednesday.