More principals and boards of trustees may soon be able to lead multiple schools under a review of education legislation.

The idea is one of a raft of changes proposed in the first review of New Zealand's education model - dubbed Tomorrow's Schools - in nearly three decades.

Other potential changes include having 5-year-olds start school in "cohorts" on set dates, rather than on their individual birthdays.

Education Minister Hekia Parata has released a discussion paper on revamping the Education Act 1989, which gave local communities responsibility for running schools instead of "centralised bureaucracy".

"However, that was 26 years ago and the world has changed since then," Parata said.

Changes suggested include removing "unnecessary red tape" from school boards, possibly having some govern multiple schools. Parata said principals themselves had expressed an interest in leading more than one school, particularly where there might be very small rolls.

Principals' Federation president Denise Torrey said increasing "flexibility" was important.

One principal moving around to lead multiple small schools had its benefits, especially in areas where recruiting experienced principals was difficult, she said.

It already worked for some schools, like Trinity Schools, a trio of integrated Catholic schools in Southland that had a joint management and governance structure.

Schools that were "doing well" could have more freedom and extra decision-making rights, but having a "graduated response" to underachievement by schools would mean earlier intervention for those not doing well, Parata said.

"In the current act they have to get in to significant trouble before intervention."

If a school was persistently underachieving, it could become a reason to have it closed, she said.

Post Primary Teachers' Association president Angela Roberts was unsure about the benefit of increasing punitive measures for struggling schools and rewarding those with high achievement.

"If a school is struggling, it isn't because they don't care, it's because they need help."

The union would "engage in good faith" in the process.

"I just hope that decisions have not been made [already], which has happened in the past."

Other suggested changes included allowing the Ministry of Education to enforce an enrolment zone on a school when it refused or was slow to do so, or allowing 5-year-olds to start school in "cohorts" on set dates, rather than on their individual birthdays.

It would be a decision for school made with their communities, the paper said.

While children were able to start on their 5th birthday, the Act could be changed to make attendance compulsory once they did start, instead of from the age of 6.

While there was no detail offered, the document mentioned creating guidelines for opening, merging, and closing schools.

Parata said the current Act was "very administratively dense", but the real emphasis needed to be on raising the achievement of students.

"The world has changed, but the Act hasn't."

It needed to enable collaboration and flexibility, with engagement from school communities, she said.

It was made clear in the discussion document that previously controversial policies regarding National Standards, charter schools, and the recently revamped teacher governing body - Education Council - were off the table for discussion.

Any changes likely to increase the Government's nearly $11 billion budget on education were also off the table, it said.

Green Party education spokeswoman Catherine Delahunty said the proposed review was a "farce" that removed anything from discussion that involved more money, or challenging controversial policies recently introduced.

The review looked like it would find new ways to blame schools in poor areas for the lower achievement of their pupils, she said.

"Schools working with the poorest children in New Zealand, and often with large numbers of kids with special needs, need more support from the minister, not more threats."

It appeared schools with wealthy children would be rewarded, while those with disadvantaged schools would be punished, she said.

New Zealand Educational Institute president Louise Green said it was good to have an opportunity to form a shared vision of what the goals of the country's education system should be.

Public consultation opened on Monday and would run until December 14.

The outcome would become known in early 2016, before a Bill was drafted and introduced to Parliament.