Australian schools are getting worse at preparing young people for life in the 21st century, falling further behind in the teaching of maths, science and reading.
The second release of international schools data in a week will form a key part of discussions between state and federal education ministers next week.
Education Minister Simon Birmingham acknowledges Australia's performance in the three-yearly Program for International Student Assessment (PISA), released on Tuesday night, was slipping.
It comes on the back of last week's Trends in International Mathematics and Science Study (TIMSS) showing Australian students still middle of the pack after 20 years of testing.
"Given the wealth of our nation and scale of our investment, we should expect to be a clear education leader, not risk becoming a laggard," Senator Birmingham said.
"We must leave the politicking at the door and have a genuine conversation that is based on evidence about what we do from here."
Australia is above the OECD average, but sits equal 10th in science, equal 12th in reading and equal 20th in maths, according to analysis by the Australian Council for Educational Research, which reports on the study.
"The PISA results are showing that we are getting worse at preparing our students for the everyday challenges of adult life in the 21st century," the council's Sue Thomson told AAP.
Dr Thomson says there is an issue with the teaching of maths and science in Australia.
"TIMSS has shown that and now PISA has shown it again," she said.
"Other countries are getting better than we are and we're not even just standing still in this one, we're falling behind as well."
More than half-a-million 15-year-olds complete the test worldwide, aimed at measuring how well they use their knowledge to meet real-life challenges, with more than 14,000 Australian students taking part.
The 2015 test, which focused on science, asked students about issues such as migratory bird patterns, running in hot weather and sustainable fish farming.
After sitting behind the likes of Kazakhstan and Slovenia in the TIMSS , Australia was outperformed by Finland in all three PISA areas, Vietnam in Science and Slovenia, again, in maths.
Singapore was the highest performer across the board.
"I don't think there is any good news stories out of it because all of the gaps that we measure have continued to have just stayed," Dr Thomson said.
A more detailed national report will be released early next year.
