"The students running around are getting lots of prickles and injuries on their feet and when the tree leaves, chestnuts and leaves fall we lose half the court space."
He says the school is planning to upgrade the court surface to astro-turf in the future.
"We want to increase the playing area and make it a safe surface for all of our students and community - we don't want anyone hurt playing underneath it."
But New Zealand Chestnut Council member Ray Knowles says it's not a good enough reason.
"I suspect the real reason why people do not like the tree is because of all the leaves, burrs and twigs that drop off it during autumn.
"Large trees are messy things and that is just the way nature has made them.
"It's a pity such a wonderful specimen has to be cut down."
He says New Zealand now has a fledgling chestnut industry based on growing nuts that can be made into a wide range of processed products.
"The planet needs more trees and that's what they should be teaching the kids."
The tree is a European chestnut - Castanea sativa - which originates from the Black Sea region in Southern Europe, he says.
"The tree looks perfectly sound and is of no more danger to anyone than any other large tree.
"It appears to be at least 100 years old and would have been planted by the early settlers to the region."
What do you think? Comment on this story on our Facebook page
We know the tree is at least 55 years old, as the Te Awamutu Courier sports editor Colin Thorsen remembers throwing chestnuts when he was a student there in the 1960s.
Mr Pentecost says the school plans to keep the memory of the tree alive and upcycle the wood.
"We want to preserve the heritage and turn a lot of the main trunks of the tree into furniture for the students to use, and will be planting another tree to replace the chestnut tree."
He says parents have been understanding and supportive of the reasoning behind the decision.
The tree will come down during the school holidays.