The Secondary Principals' Association is refusing to endorse tomorrow's climate change march and says students are likely to be marked as truant if they attend the protest.
Principals have told RNZ while the march's message is commendable, they cannot guarantee students' safety if they decide to attend.
With thousands of students across the country expected to take part in the Schools Strike for Climate Action, many schools feel they're in a very tricky position.
The principal of Mount Albert Grammar School in Auckland, Patrick Drumm, wrote to parents this morning saying he had significant safety concerns for students if they go to the strike.
He said the police shared his concerns because there has been a lack of information from organisers.
"We just haven't had any feedback as a school from organisers around what is planned for tomorrow," he said. "So it becomes pretty impossible and impractical for the school to endorse people being away."
Mr Drumm said tomorrow will be business as usual and he expects children to be at school for a full day of learning.
Secondary Principals' Association president Mike Williams agreed and is also worried about the students who choose to go.
"Young people might be taking public transport and that is all good," Mr Williams said. "But they might be driving in their friend's car which has no warrant and the driver has no full licence or any licence.
"So the risks just go up and up and up."
Mr Williams said principals simply cannot guarantee the safety of the students.
"If the parents think we have endorsed it, they could well believe that we think it is going to be okay and we have checked it out and we think the kids will be safe," he said.
"But there are a whole pile of issues around the children getting there, when they are there, who is supervising, what will happen and we have no control over that."
He was aware some teachers were taking students to the events as part of organised trips - which he said was fine. But he believes the rally is more about publicity, rather than making any real change.
"There are lots of ways of putting pressure on," he said. "A protest is one, it is global, it has got the newspapers, it is good, but what happens next?
"Or is that just the fish and chips wrappers for next week?"
It is a similar story for the Canterbury / West Coast Principals' Association.
President Phil Holstein said while it is great the students are engaged, there are better ways to make a point.
"The intention is honourable, it is a significant global issue and we are all very conscious of it," Mr Holstein said. "It was just concerns around the timing."
Mr Holstein is the principal at Burnside High School in Christchurch, where he said his students are taking action at school.
"A petition is going to be available for our children to sign here," Mr Holstein said. "And the sustainability group is going to be leading that.
"And the commitment by that group is they are going to be taking it to the key figures in Christchurch that matter and table it there."
The Secondary Principals' Association said the strike should have been better organised and schools should have been involved in the planning. That way, more students could have been part of it and had the backing of their schools.
In a statement, the Ministry of Education said there is no one size fits all approach to attendance and truancy.
It said while awareness of the environment for students is important, it is up to each Board of Trustees to decide whether going to the climate events is marked as truancy or not.