According to a 2021 Australian Education Union survey, 62% of teachers say NAPLAN - the national literacy and numeracy test for years 3-9 - is an ineffective diagnostic tool.

Those who use NAPLAN results to inform education reform, however, say it provides important insight into how kids are doing at school and that a sharp decline in students doing the test is a cause for concern.

So what does this all mean, and how useful is NAPLAN data to begin with?