Leading teachers can be rewarded for extra responsibility through funding units worth $4,000 each. But that had not been enough to keep the best, Ms Ala'alatoa said.
"The units that we currently have are not enough for people to be thinking that there is a long-term career inside a classroom."
In Bucklands Beach, teachers and school management at Macleans College monitor achievement data, at a student and classroom level, in order to identify and spread good teaching.
Principal Byron Bentley said the new roles would help entrench that process.
As a next step, he said, executive principals should be involved in the training of those due to step up to school leadership roles.
"That's a very important area, you can't just leave it to chance or to come out of nowhere."
Education Minister Hekia Parata yesterday moved to clarify how the new school leadership roles - executive principals, expert teachers, lead teachers and change principals - would work. The positions will not be put in place at every school, and not fully implemented until 2017.
Struggling schools can apply to the Government for an allowance of $50,000 to add to the salary they can offer principals.
Many schools placed under intervention by the Government for poor performance are small and rural, but Ms Parata said that prospect would not be a barrier to most principals.
Executive principals will be given time and money to provide leadership across an average of 10 schools while remaining at their own.
Ms Parata said groupings were likely to follow student progression from primary to intermediate to secondary schools.
She said the roles were partly a response to education sector requests, including union proposals in conference papers.
Change at the top
• Strongest teachers are already identified and promoted at many schools.
• New funding will strengthen that process, and offer better career progression.
• Principals at poorly performing schools will not be turfed out, Government promises.
• New roles partly in response to education union proposals.