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High school teachers will go on strike for a day and are threatening more industrial action including more strikes, marking bans and refusals to take overcrowded classes.
Secondary teachers in pay negotiations with the Government gave notice yesterday of a national strike on September 12, if they don't get an improved offer on their pay claim.
The strike will be the first of its type since 2002.
Many high schools are likely to ask students to stay home for the day. Others may offer a scaled-back programme run largely by non-union member staff.
The industrial action comes amid lengthy negotiations between the Ministry of Education and the Post Primary Teachers' Association, which represents about 90 per cent of high school teachers.
Union members were seeking a 7.5 per cent pay rise, a 30-student cap on classes, additional pay for teachers with extra responsibilities and equitable non-teaching time for part-timers.
The one-year claim was lodged last week .
The union earlier asked for a 12 per cent hike over three years but almost unanimously rejected the ministry's offer of 10.25 per cent over three years.
Secondary Principals' Association president Peter Gall said he was disappointed a settlement had not been reached.
The planned strike would be disruptive for schools, especially as it coincided with practice exams for senior students at some schools, he said.
PPTA president Robin Duff said the association hoped the ministry would give a "substantially improved" response and the planned strike could be avoided.
He said the sector needed to increase pay to attract good-quality graduates and adequately equip them in the classroom.
"We need to make secondary teaching a job that people want to do," said Mr Duff. "Highly qualified and effective teachers with time to bring out each student's potential are essential to ensure that our children can participate in a brighter future."
High school teachers on strike next month will vote on an action plan for the rest of the year, which could include more national strikes or rolling strikes.
Other measures being considered included withholding National Certificate of Educational Achievement (NCEA) marks or refusing to mark the external exams, not teaching classes with more than 30 students and not coaching sport after school unless paid.
Secretary for Education Karen Sewell said the ministry had been bargaining in good faith and doing everything it could to bring about a resolution in this year's bargaining round with the PPTA.
After making two offers to the PPTA, the ministry was "very disappointed" at the strike threat.
Ms Sewell said hearing of such an announcement before a return to negotiations was disheartening, and it would not resolve the situation.
The ministry had approached the Department of Labour to assist with mediation in a bid to get both sides talking.
"We're dismayed and disappointed that the PPTA has chosen this action after only six days of negotiating."
WHAT'S CLAIMED
* 7.5 per cent pay rise.
* Cap classes at 30 students.
* Improved pay for teachers with additional responsibilities.
* Equitable non-teaching time for part-timers.
- additional reporting NZPA