Preliminary data from this year's NAPLAN tests reveal negligible improvement, with federal Education Minister Simon Birmingham calling for a fresh approach to teaching young people.

"We need to focus on evidence based measures that will get results for our students because today's results once again show that, despite significant funding growth, we are not getting sufficient improvements in student outcomes," he said.

The 2016 results show reading scores have increased by 0.4 per cent since 2013, writing scores have declined by 0.2 per cent and numeracy scores have risen by 1.26 per cent. Over the same time period, federal school funding has increased by 23.7 per cent.

"We have excellent schools and teachers in Australia that successfully set the vast majority of our students up for life but we need to move the conversation on from just how much is being spent in schools to focus on how record funding can best be used for the benefit of students," Mr Birmingham said.

Long term data shows students have made overall gains since NAPLAN testing was introduced in 2008, but the Australian Curriculum, Assessment and Reporting Authority chief executive Robert Randall said the recent stagnation in results was a concern.

"Plateauing results are not what we should expect or assume from our education systems," he said.

"Literacy and numeracy are the foundations of learning in and beyond school. Literacy and numeracy achievement needs to improve to ensure the wellbeing of individual students and the country as a whole."

Grattan Institute school education program director Peter Goss said it could take some time for investment in education to result in student improvement.

"It takes three to five years for change in practice to clearly show up in a change in learning," he said. "Sometimes it can take up to seven years to turn a school around."

Australian Education Union federal president Correna Haythorpe stressed the importance of continuing the needs-based funding recommended under the Gonski review.

"The single biggest problem in Australian education remains the unacceptable gaps in achievement between students from different backgrounds and locations," Ms Haythorpe said.

"The evidence shows delivering the full Gonski funding is our best chance to ensure all schools are properly resourced to meet the needs of all kids and address these achievement gaps."

University of Melbourne education expert Professor Patrick Griffin said reforming teaching practice would lift student performance.

"Some schools are making great progress by changing teaching practice," he said. "But it's one thing to make a change and another to sustain it."

NSW Premier Mike Baird has identified lifting the state's NAPLAN results over the next three years as a priority.

The director of teaching and learning at Sydney Catholic Schools, Michael Bezzina, said while NAPLAN results were one measure of performance, it was more important to focus on individual student gain.

"For us, it's not so much about the destination but the distance travelled," he said.

Carolyn Parsell is the principal of St Joachim's Catholic Primary School in Lidcombe, where students recorded outstanding gains in the 2015 NAPLAN tests. She credits this to continued support from teachers, learning support staff, parents and volunteers from the community.

"It took really intensive work that was done through intervention and support and really close monitoring of students and their outcomes," she said.

"We looked at where they are, what they need to learn and targeted their needs appropriately."

Individual students will receive their results from mid-August, a process likely to be quicker from next year when online testing starts to roll out across the country.