Collegiate teachers Chris Buckley and Costas Thrasyvoulou shaved each other's heads on Friday to raise money for Brain Tumour Support New Zealand.
The initiative was in honour of Collegiate's head of maths, John Dalman, who died during the last school holidays.
Dalman began at the school in 2014.
"John was a real gentleman," Buckley said.
"He was still doing extra tutoring in the evenings, right up until the end of last term."
Year 13 students Shaun O'Leary and Adam Beard organised the initiative as part of Grey House's Charity Week.
Close to $5000 had been raised so far.
"Basically, people could pay for us to shave our heads," Beard said.
"Mr Thrasyvoulou took it into his own hands to raise money for Mr Buckley, and between them we raised $500.
"Around 50 of us in Grey got the trim, pretty much the whole house. That includes the housemaster as well."
Beard said the initiative had extra meaning for him, because he lost an aunt to a brain tumour two months ago.
Grey housemaster Andrew Brunt was on hand on Friday - sporting a freshly shaved number one haircut.
"I'm a part of them, so it made sense for me to get involved as well," Brunt said.
"Something like this is about raising awareness as well as money.
"The boys in Grey have been doing 38 burpees every morning, because the five year survival rate for someone with brain cancer is only 38 per cent.
"It's a pretty serious disease."
To donate to Grey House's fundraising initiative, go to: