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A study of nine schools funded by private backers in Australia found they were built more quickly and freed up principals to spend time focusing on education rather than problems with the buildings.
The primary and secondary schools opened in New South Wales 2004 and 2005, designed, funded and constructed by a corporate consortium.
However, teachers and principals criticised the design standards of buildings set by Department of Education and Training.
The Australian Government expected to save $10.4 million over the project's 30-year life - or just over 7 per cent on the cost of the traditional state model.
The National Party is considering using private developers to build and own new state schools in a controversial proposal lampooned by Education Minister Steve Maharey.
The Ministry of Education predicted Auckland will need up to 40 new schools in the next 20 years to cater to population growth.
Mr Maharey said the Australian experience did not easily translate to New Zealand.
He said the cost savings predicted across the Tasman would not be as big in New Zealand as the Government in New Zealand had money put aside.
"We can borrow money at a lower rate, and therefore build schools at a lower rate."
He said Labour was committed to keeping public ownership of all state schools.
"You may well save some money on the initial putting up of a school in [Australia]," said Mr Maharey.
"But over time the people are looking for a rate of return on their investment and they find one way or the other of doing it - whether it's on maintenance or whether it's on what they do with expansion of the school or the way they service the school."
National Party education spokeswoman Katherine Rich said the proposal was mainstream Labour policy in the UK and Australia. She said 10 more of the schools were being developed in New South Wales and the state of Victoria was looking at the option.
The UK will have 80 academies, or independent state schools, open by autumn this year with a further 50 expected next year, said Ms Rich.
Quality Public Education Coalition national chairman John Minto said overseas experience showed the profit-driven private sector cut corners and cut quality in public schools.
"Involving the private sector in public schooling overseas has never resulted in improved educational outcomes," he said.
A New South Wales Treasury review of the New Schools Project - the first privately financed schools in Australia - found the nine schools were delivered two years earlier on average than if traditional public sector funding was used.
The review, released last year, said the construction period of the schools was about three months faster.
Under the contract, the private sector backer is responsible for services such as cleaning, maintenance and security until the end of 2032, when the buildings will be handed to the Department of Education and Training.
The review found it had an an "unanticipated benefit" of freeing up principals from maintenance or security demands.
Dr Joce Jesson, a principal lecturer in University of Auckland's social and policy studies school, said the on-site managers were glorified caretakers.
She questioned the motives of the private sector.
"You immediately want to know why would anyone want to do this unless they are going to make a decent profit," said Dr Jesson.
NZ Council for Infrastructure Development chief executive Stephen Selwood said public private partnerships could provide good value and high accountability if done well.
He said an Auditor-General's Performance Audit of the New South Wales schools showed savings of between 7 per cent and 23 per cent.