A charter school's new $100,000 waka has sparked outrage among teacher unions.

The He Puna Marama trust, which owns two charter schools in Whangarei, bought the 22-person carved waka to be used mainly in its primary school Te Kapehu Whetu, for health and fitness studies.

But New Zealand Educational Institute national president Louise Green says the spending is totally extravagant.

"If the charter schools are receiving enough money for the government to actually be able to afford a resource like this, they're getting too much public funding.

"And at the same time, we've got our state schools that are crying out for more funding."