NAPLAN growth, not just NAPLAN scores.
Every results season reports how this year's Year 9s compare to last year's Year 9s. ACARA also publishes a different measure that almost nobody reports: the same cohort of students, tracked from Year 3 to 5, 5 to 7, and 7 to 9. That is the only NAPLAN number that answers how much a student actually improved.
Victoria’s NAPLAN growth rate is not distinguishable from the national average in any of the fifteen comparisons we checked — despite Victoria leading on absolute scores.
Checked across all three tracked-cohort transitions and all five domains — fifteen comparisons in total.
The method, stated plainly
ACARA’s Cohort gain data publishes a value and a confidence interval for each state’s average score gain — but, unlike the State and Subgroup comparison tabs behind our results-Victoria page, it does not publish its own significance classification. So this page uses a plain, checkable test instead: if Victoria’s confidence interval and Australia’s confidence interval overlap, the two rates cannot be told apart. That is our test, not an ACARA classification — and it is stated here so any figure below can be verified against the source file.
All fifteen comparisons
Victoria’s point estimate is often the higher of the two — in Numeracy, Year 7 to 9, Victoria gained 38.1 points against Australia’s 34.0. But every comparison’s confidence intervals overlap, in every domain, at every transition checked.
| Domain | Victoria | Australia | Overlap? |
|---|---|---|---|
| Reading | 80.0 ± 5.8 | 83.4 ± 5.3 | Yes |
| Writing | 73.9 ± 8.3 | 65.9 ± 8.1 | Yes |
| Spelling | 87.3 ± 4.2 | 87.4 ± 3.8 | Yes |
| Grammar & punctuation | 90.9 ± 7.6 | 88.3 ± 7.1 | Yes |
| Numeracy | 91.1 ± 4.9 | 89.9 ± 4.4 | Yes |
| Domain | Victoria | Australia | Overlap? |
|---|---|---|---|
| Reading | 40.4 ± 6.6 | 43.0 ± 5.9 | Yes |
| Writing | 56.6 ± 8.7 | 50.4 ± 8.3 | Yes |
| Spelling | 53.2 ± 4.1 | 55.1 ± 3.4 | Yes |
| Grammar & punctuation | 38.7 ± 8.2 | 36.7 ± 7.5 | Yes |
| Numeracy | 60.9 ± 5.9 | 58.9 ± 4.8 | Yes |
| Domain | Victoria | Australia | Overlap? |
|---|---|---|---|
| Reading | 26.4 ± 6.7 | 27.1 ± 5.5 | Yes |
| Writing | 34.5 ± 9.3 | 31.7 ± 8.4 | Yes |
| Spelling | 30.3 ± 4.4 | 28.5 ± 3.4 | Yes |
| Grammar & punctuation | 20.7 ± 8.2 | 17.5 ± 6.7 | Yes |
| Numeracy | 38.1 ± 7.4 | 34.0 ± 5.5 | Yes |
15 of 15
every Victoria-vs-Australia growth comparison checked overlaps — none is distinguishable at this confidence level.
This does not mean Victorian schools are not doing well — a student in Victoria still finishes with a higher average score than the national figure, because Victoria’s starting position is also higher. It means the rate of improvement, once a student is enrolled, tracks the national rate closely enough that the difference cannot be told apart from noise with the confidence intervals ACARA publishes. The state advantage in scores is not obviously a state advantage in how fast students grow.
What this means for your child
A single year’s NAPLAN score says where a student stands. It cannot say whether they are improving faster or slower than typical — that needs the same student compared across two sittings, which is exactly what a school or family can do informally by comparing two reports side by side, the same way this analysis compares two years of state averages. State-level growth data being unremarkable is not a reason to stop watching a specific child’s trajectory — it is a reason not to read a single year’s state ranking as a growth story it was never designed to tell.
Sources
- Australian Curriculum, Assessment and Reporting Authority (ACARA), NAPLAN national results dataset, 2026.Every score, percentage, effect size and classification quoted across these pages.
- ACARA, NAPLAN proficiency level descriptions.Definitions of the four levels: Needs additional support, Developing, Strong, Exceeding.
- ACARA, NAPLAN 2025 Technical Report, pp. 86–87.The effect-size and nature-of-difference methodology: the 0.2 and 0.5 thresholds separating “close to”, “above” and “substantially above”.
- ACARA, NAPLAN (National Assessment Program), and the Victorian Curriculum and Assessment Authority, NAPLAN assessments.What the assessment is, who sits it, and how it is administered in Victoria.
- Cohort gain figures and the confidence-interval-overlap test are registered as TST-15in the practice’s evidence register, including the methodology caveat about ACARA’s classification columns.