New Zealand's education system is world-leading, but its performance has plateaued and it needs a system-wide lift, the Minister of Education says.

Minister Hekia Parata made the comments in a speech to principals in the final day of the New Zealand Educational Institute principals' conference in Nelson.

More than 100 principals from around the country were at the Rutherford Hotel for the three-day conference, where they heard from speakers, attended workshops and visited local schools.

Ms Parata gave a short speech yesterday on the challenges facing the sector.

New Zealand was seventh out of 65 OECD countries in the 2009 Programme for International Student Assessment study.

Four out of five students were succeeding in the education system, taking away a qualification to move to the next phase of their lives, she said.

The six countries ahead in the rankings - Singapore, Hong Kong, Shanghai, China, South Korea, Finland, Canada - were behind New Zealand five years ago.

"Standing still is slipping behind," she said.

The disaggregated results of the PISA 2009 study showed New Zealand pakeha as second in the world, but Asian New Zealanders were seventh, Maori New Zealanders were 34th, and Pacifica New Zealanders were 44th, she said.

"New Zealand was unique in being identified as a very high-performing education system with very low equity.

"Unless we get a system-wide lift in achievement we will continue to have an average that masks the challenges."

With the advent of the New Zealand Qualification framework and the underlying assumption that every learner could be successful, four out of five children succeeding was no longer good enough, she said.

"We are a highly ambitious government, we are highly aspirational, as indeed all of you are.

"That's why our education plan is how do we get five out of five."

Principals and teachers needed to take advantage of the permissiveness of the curriculum to design a programme that suited their students.

The Education Review Office had said fewer than 25 per cent of schools were using the curriculum to its full potential.

She also discussed National Standards, saying the data should form the basis of a conversation about the learning of a child, and be contextualised with other information.

One of the characteristics of high-performing education systems around the world was the quality and use of data and information, she said.

"This idea that students have to be labelled as failures is offensive to me and I'm sure it is offensive to you too, because no professional would be using that language if what they were aiming to do was raise achievement."

Assessment data should instead be used in real-time as a way of driving teaching practice, rather than being used at the end of the process to judge whether someone passed or failed.

The ministry needed the overall data to know where to prioritise resources and where to focus, she said. The data from the first year was variable, but not inaccurate or invalid.

"Why wouldn't it be? It is the first year, everybody used the format they chose to use. But we have a journey ahead of us to grow the quality of that information."

- © Fairfax NZ News