St Therese Catholic Primary School vs The Illawarra Grammar School
A head-to-head comparison of two schools in New South Wales, 248 m apart, using official ACARA 2025 data. Best value in each row is highlighted.
St Therese Catholic Primary School
Mangerton · Catholic primary · K-6
368 students · ICSEA 1090
The Illawarra Grammar School
Wollongong West · Independent combined · K-12
970 students · ICSEA 1159
| Measure | St Therese Catholic Primary School Mangerton NSW | The Illawarra Grammar School Wollongong West NSW |
|---|---|---|
| Success Index | 70 Top 25% | 80 Top 10% |
| State rank (type) | #298 of 1,619 | #44 of 314 |
| National rank (type) | #983 of 4,908 | #107 of 1,259 |
| Sector | Catholic | Independent |
| Type | Primary | Combined |
| Year range | K-6 | K-12 |
| Students | 368 | 970 |
| Girls / boys | 192 / 176 | 464 / 506 |
| Foundation intake | 60 | 49 |
| Year 7 cohort | – | 106 |
| Year 12 cohort | – | 92 |
| VCE median study score VCAA, latest year | – | – |
| VCE study scores 40+ | – | – |
| 5-year enrolment growth | +3% | +23% |
| ICSEA Average 1000 | 1090 | 1159 |
| ICSEA percentile | 81th | 96th |
| Top SEA quarter | 36% | 64% |
| Bottom SEA quarter | 8% | 2% |
| Students per teacher | 16.7 | 9.7 |
| Teaching staff (FTE) | 22.0 | 99.8 |
| Non-teaching staff (FTE) | 7.9 | 45.4 |
| Language background other than English | 17% | 36% |
| Indigenous students | 2% | 2% |
| Suburb | Mangerton 2500 | Wollongong West 2500 |
| Council area | Wollongong | Wollongong |
| Remoteness | Major Cities | Major Cities |
| Website | www.stwwdow.catholic.edu.au | www.tigs.nsw.edu.au |
The verdict
- •The Illawarra Grammar School scores higher on the Success Index (80.3 vs 70.4).
- •The Illawarra Grammar School has the higher ICSEA (1159 vs 1090), indicating a more advantaged community.
- •The Illawarra Grammar School has fewer students per teacher (9.7 vs 16.7).
- •The Illawarra Grammar School is the larger school with 970 students compared with 368.
- •The Illawarra Grammar School has grown faster over five years (23% vs 3%).
- •St Therese Catholic Primary School is a catholic school while The Illawarra Grammar School is an independent school, so fees and enrolment rules differ.
The Success Index summarises community advantage, resourcing and momentum from ACARA data. It does not measure teaching quality, results or fit. Methodology.
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Frequently asked questions
Is St Therese Catholic Primary School better than The Illawarra Grammar School?
On the Success Index, The Illawarra Grammar School ranks higher (80.3 vs 70.4 out of 100). The index measures community advantage and momentum from ACARA data, not teaching quality, so visit both schools before deciding.
How far apart are St Therese Catholic Primary School and The Illawarra Grammar School?
About 248 m in a straight line, between Mangerton and Wollongong West in New South Wales.
Which has the better student-to-teacher ratio?
St Therese Catholic Primary School has 16.7 students per full-time-equivalent teacher and The Illawarra Grammar School has 9.7.
How do St Therese Catholic Primary School and The Illawarra Grammar School rank in NSW?
St Therese Catholic Primary School is 298th of 1,619 and The Illawarra Grammar School is 44th of 314 among primary schools in New South Wales on the 2025 Success Index.