A private school run by the Brethren religious group has become the largest to apply to join the state sector as an integrated school.
Westmount School has 1600 students scattered across 24 sites from Northland to Southland. The Education Ministry says it is preparing a report on the application for the Education Minister.
The Westmount Education Trust says integration has worked well for Catholic, Jewish and Islamic schools and would be good for Westmount School.
It says it would give the school greater opportunities to share its teaching methods and allow its students to benefit from increased resources.
However, the Post Primary Teachers Association and the Educational Institute oppose the application.
They say government funding for the school will leap from $2.3 million a year to more than $9 million, and that money would be better spent elsewhere.
Post Primary Teachers Association president Angela Roberts says the funding won't help the Maori, Pasifika and low-income children the Government wants to help most.
Educational Institute secretary Paul Goulter says the state system cannot afford another school.
"This is going to come into a state system that's already underfunded and it's really having difficulty with existing levels of resources, and here's another group of students coming in and that will place even more pressure on it," he says.
Mr Goulter says the Educational Institute is suspicious of the integration process because the Government late last year agreed to integrate Wanganui Collegiate, even though there is no need for more state school places in Whanganui or the surrounding region.