Science Extension — NSW HSC scaling 2024

UAC's verbatim 2024 scaling for Science Extension. 753 students sat this course. Median scaled mark 32.6; top-decile (P90) scaled 40.9; cohort scaled mean 32.2 (out of 50 per unit).

Scaled marks distribution

Percentile	HSC mark	Scaled mark
P99 (top 1%)	49.0	48.0
P90 (top 10%)	44.0	40.9
P75 (top 25%)	42.0	37.1
P50 (median)	39.0	32.6
P25 (bottom 25%)	36.0	27.8

Summary statistics

	HSC mark (raw)	Scaled mark
Mean	38.5	32.2
Standard deviation	4.8	7.1
Maximum	49.0	49.2
Students (2024)	753

How Science Extension scaled in 2024

This subject scales up. The candidature performs slightly above the cohort median across all subjects, so raw marks are adjusted upward in the scaling process. A typical raw mark scales to a slightly higher scaled mark.

For Science Extension specifically, the scaled distribution runs from P25 of 27.8 to P90 of 40.9 — a spread of 13.1 scaled points between the bottom and top quartiles of the cohort. That spread is the practical room for movement within this subject: a student who moves from the bottom quartile of Science Extension to the top decile gains roughly 13 scaled points per unit, which is significant when multiplied across 2 units toward the ATAR aggregate.

The gap between HSC mark and scaled mark at P90 was -3.1. That gap is negative — top-performing Science Extension students were scaled down in 2024. This is what scaling actually does: it's not a percentage multiplier; it's a candidature-position adjustment.

3-year scaling trend for Science Extension ↓

Year	Scaled mean (/ 50)
2022	33.8
2023	—
2024	32.2

Scaling has fallen by 1.6 points over 2 years (2022: 33.8 → 2024: 32.2). This typically reflects a weakening candidature — the average student in this subject is performing relatively less well in their other courses than they used to.

3-year trend data sourced from the UAC annual scaling reports 2022–2024. See all scaling trends.

Tutor rate context for Science Extension

Subject complexity classification: medium. Based on our subject-complexity model, this subject typically carries a no uplift adjustment to the base AU tutor rate band — partly because of the qualified-tutor pool size, partly because of subject-specific marking and exam complexity.

Tutor tier	Typical rate for Science Extension
University-student tutor	$60/hr
Experienced graduate	$80/hr
Registered teacher	$110/hr
Subject specialist	$140/hr

Estimates from the AU rate synthesis at /rates/. Use the rate estimator to add city and delivery format.

How to read the distribution

The HSC mark column shows the raw HSC mark you would have needed to sit at each percentile of the Science Extension candidature in 2024. The scaled mark column shows what that performance was worth toward your ATAR aggregate. The two values diverge because scaling reflects the academic strength of the candidature as a whole — it is not a fixed conversion of raw HSC mark to scaled mark.

The same HSC mark can produce a range of scaled marks (because students with that HSC mark may have different positions in the underlying cohort). This is why UAC publishes a distribution rather than a lookup table.

Caveats specific to Science Extension

• This is 2024 data. UAC recomputes scaling each year — 2025 figures will move if the candidature mix changes.
• The HSC mark on your transcript is the NESA-reported HSC mark (aligned to course standards). The mark used in scaling is the raw HSC mark, which is not reported to students directly.
• For courses with combined candidatures (English Standard / Advanced / Studies share a common scale via the NESA standards-aligned raw marks), UAC's scaling treats the combined group; per-course reporting is for transparency.
• Use the scaling data to understand the system, not as the only input to subject selection. Subject engagement matters more than scaling pattern at every level except perhaps the very top decile.

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