Three schools in Tokoroa have been vandalised overnight, with up to half the windows at some schools being smashed.
It is understood at least one of the schools affected has had to change its classes for the day.
Tokoroa Central School principal Debbie Follas said half the windows at her school had been smashed.
"I was rung by a staff member this morning to say that a number of windows and glass doors were smashed."
She said those responsible did not appear to have tried to enter buildings, and nothing had been stolen
However, the damage would cost thousands to repair.
"It is really disappointing, it is upsetting for our school community and our staff and students."
Staff had to spend the morning vacuuming up glass, she said.
Police were notified and conducted scene examinations and were reviewing CCTV footage.
Senior Sergeant Jason Henderson said it was "an act of pointless destruction that is costing schools and our community large amounts of time and money."
David Henry School was also believed to be affected, as were a number of local businesses.