The NSW curriculum review will aim to arrest an "unmatched" 20-year decline in Australian students' results in international tests by finding ways to stop students from falling behind year after year.
"In the [early 2000s] students in NSW were performing among the highest in the world but over the period since the turn of the century there's been a significant decline," said Professor Geoff Masters, who is leading the review, which is the biggest shake-up in 30 years and is due to be finalised this year.
"That decline is almost unmatched in the rest of the world, it's very hard to find places that have seen such a steady decline over such a long period," Professor Masters told The Sydney Morning Herald Schools Summit on Thursday.
"I believe that the reform of the curriculum is one of the factors that can arrest the decline and turn it around."
Australian students' performance in the OECD's Programme for International Student Assessment last year fell below the international average for maths for the first time since the tests began and scores in all domains have declined significantly in both real and relative terms.
Premier Gladys Berejiklian said the results challenge "all of us to rethink our approach to education so our students can reach their full potential and also so our economic future can be assured".
Draft recommendations from the review, which Professor Masters handed down late last year, called for cuts to the number of HSC subjects, a shift to micro-credentials to reduce the emphasis on end-of-year exams and merging vocational and academic subjects.
Ms Berejiklian said the draft recommendation that syllabus content be reduced by about 30 per cent needed to be a "benchmark for change" to the education system.
Professor Masters said his discussions with teachers and students also highlighted the need to increase student engagement and make sure syllabuses are flexible enough to cater to students at the highest and lowest levels in any year group.
"A typical kind of comment from a teacher was 'currently in the education system for a majority of young people you see a lot of eyes glazing over'," Professor Masters said.
"Many teachers who spoke with the review were concerned with the level of engagement and the number of students falling behind who don't see significant meaning of what they're being taught."
Professor Masters said reducing the breadth of content to give students the chance to apply core concepts in practical situations was one way the review will aim to improve engagement.
He said making syllabus progression "competence-based rather than time-based" would also be a key strategy.
"The syllabuses that we currently develop are anchored to time periods...when they finish a particular year of school they move on to the next curriculum whether they're ready or not," Professor Masters said.
"That happens year after year and they fall increasingly far behind as they move through the school years."
He said that NAPLAN data that shows the least advanced students in each year group are up to six years behind the most advanced students, highlighting the need to move away from an age-based curriculum model.
Professor Masters said change to the degree being proposed by the curriculum review is "not without risk" but that doing nothing will mean that issues around low engagement and students falling irretrievably behind will persist.