More than 1000 year 9 students across Northland went without lessons as teachers took the first step in a month-long series of proposed industrial action.
The Post Primary Teachers' Association - the union representing secondary school teachers and principals - announced last week it would take "rostering home action" which will see teachers opt not to teach a certain year group on a particular day, over four weeks.
It began yesterdaywith year 9 students and is scheduled to continue with Year 10 students on June 11, Year 11 on June 25 and Year 12 on July 12.
Ministry of Education figures for 2019 show there are 1770 year 9 students enrolled in schools in the Te Tai Tokerau region.
The industrial action comes after secondary school, primary school and area school teachers joined forces for a mega-strike last week.
Rachel Burnett, Dargaville High School English teacher and PPTA Northland Lower Regional chairwoman, hoped the planned industrial action would show the Government teachers were not going to stop until "meaningful changes" were made.
"We must make changes to ensure that our kids are taught by qualified professionals and that teachers are supported enough to stay in their jobs."
Ellen MacGregor-Reid, Ministry of Education deputy secretary, said given the action only affects one year group at a time and will not affect the full school day for teachers, striking teachers will still be getting paid.
The PPTA has also planned rolling industrial action for the week starting Monday, June 17, and Northland teachers and principals are up first to strike.
Burnett said teachers shared the frustrations some parents had.
"We also wish it hadn't got to this point and we would much rather be teaching their kids.
"I would also warn parents that if changes are not made, it is more than likely that their children will go through school having never been taught by a subject specialist," she said.
Education Minister Chris Hipkins has invited the PPTA and the NZ Educational Institute to talks with him and Ministry of Education officials tomorrow.
Burnett hoped the urgency and the importance of teachers' claims would be acknowledged during that meeting.