The Government is spending a record $9.7 billion on education, she said, but achievement levels were below the 85 to 100 per cent New Zealand needed. The most successful funding systems narrowed the gap between high-achieving rich kids and under-achieving poor kids by "strongly incentivising" pupil progress, she said.
The Government did not want to fund schools according to their raw results in National Standards or NCEA, but on how much teachers had helped students to learn over the course of six months or a year, "the consistency and the progress".
"You've got to work out which school is delivering achievement, which schools are focusing on how they raise the quality of their teaching and leadership practice, and how is that translating into kids demonstrating that they're learning more?"
After learning of Parata's comments, the teacher unions raised concerns at private meetings with her. She assured them she was merely exploring funding options this year, they say, and would go into more detail next year.
Post-Primary Teachers Association president Angela Roberts said she would be disappointed with any quick-fix approach. "It may be quick and easy to rank schools on their NCEA or National Standards results - but just because something's easy doesn't mean it's right."
New Zealand Educational Institute national secretary Paul Goulter said Parata's proposal was a "radical shift" to performance funding, which had failed in the US. He said the Government should invest in schools and pupils who needed help to achieve - not extra funding to those who were already succeeding.
Principals' Federation vice president Denise Torrey said she agreed it was time to find a new way of funding schools but performance funding was not the answer.
"National Standards are a blunt instrument. We hope she will engage with the profession - people who know how schools run - not just the Treasury boffins."
Quandary: How to judge progress
Mt Roskill's May Rd School gets more targeted funding than most others because its pupils come from neighbourhoods with low-income, immigrant families.
But principal Lynda Stuart says the $497-a-pupil decile funding is "never enough" to provide all the remdial assistance.
However, she does not believe funding the school according to pupil progress is a better system.
Stuart says the National Standards regime is the only tool for measuring progress.
There was no good way to measure tiny steps her pupils made. " We have a little boy who we really struggled to have attending school regularly.
We started up a bilingual Samoan classroom, and that little boy now attends school every day because he and his mum have a community around them.
"Now he wants to be a teacher. How do you measure that and compare the raw data to children in other schools?"