A Tauranga principal says children's educations are being treated like an experiment with the introduction of charter schools.
The first charter school could open as soon as term one next year after The Education Amendment Bill was passed in Parliament on Tuesday night.
Ian Leckie, Tahatai Coast school principal and immediate past president of teachers union NZEI, said the result represented a huge step backwards for public education.
"We have one of the best public education systems in the world; others come to us to see what we're doing. Why would you jeopardise that?
"Certainly we are saying improve the education system but where charter schools have been introduced overseas they have not worked. Many are much worse than their public school counterparts."
Mr Leckie called charter schools little more than a business model. "They are a profit-making venture, employing non-registered teachers to get hold of government education dollars.
"We have got a broad range of schools already. Nobody has yet been able to answer the question why we need charter schools."