Mount Maunganui Intermediate was yesterday closed for health and safety reasons after the twister caused extensive damage.
Principal Lisa Morresey said along with a trampoline from a nearby house flying through the front window of the administration block, donated pohutakawa trees being reduced to stumps and a $5000 shade sail being destroyed, the worst damage was to the school's new $120,000 astro turf.
"It's incredibly sad as we have been doing a considerable amount of work over the past few years to improve our student amenities. To see our new astro turf, which was only completed in December, ripped up and fences buckled and the hockey goals also damaged is absolutely heartbreaking," she said.
Mrs Morresey said two more trampolines landed in the school grounds from neighbouring properties and part of a roof from a nearby house ended up outside the school's front entrance.
Mrs Morresey said she was grateful the tornado did not strike during the school day.
"I think we have been incredibly lucky as it could have been a lot worse."
Mrs Morresey said she was heartened by offers of help, which had flooded in from the community. "People have been amazing and we hope to be able to reopen the school on Monday."
Year 8 pupils Molly Shivnan and Sam Jones, both 12, were dismayed by the extent of the damage and immediately volunteered to be part of the clean-up team.
Sam said he had seen tornadoes on TV but to see the damage they could cause first hand was "quite shocking".
Molly said: "It's very sad but I'm so grateful no buildings at our school were badly damaged and no-one was injured or killed."
Education Ministry personnel were at the school assessing the damage yesterday before the clean-up started.
Mrs Morresey said she wanted to pay tribute to Tauranga City Council's staff and maintenance contractors, who swung into action quickly.