Our Lady of Mercy College vs Our Lady of Sion College
A head-to-head comparison of two secondary schools in Victoria, 8.7 km apart, using official ACARA 2025 data. Best value in each row is highlighted.
Our Lady of Mercy College
Heidelberg · Catholic high school · 7-12
1,175 students · ICSEA 1111
Our Lady of Sion College
Box Hill · Catholic high school · 7-12
930 students · ICSEA 1111
| Measure | Our Lady of Mercy College Heidelberg VIC | Our Lady of Sion College Box Hill VIC |
|---|---|---|
| Success Index | 77 Top 10% | 76 Top 10% |
| State rank (type) | #50 of 348 | #63 of 348 |
| National rank (type) | #118 of 1,472 | #136 of 1,472 |
| Sector | Catholic | Catholic |
| Type | Secondary | Secondary |
| Year range | 7-12 | 7-12 |
| Students | 1,175 | 930 |
| Girls / boys | 1,175 / 0 | 930 / 0 |
| Foundation intake | – | – |
| Year 7 cohort | 203 | 183 |
| Year 12 cohort | 193 | 140 |
| VCE median study score VCAA, latest year | 33 | 32 |
| VCE study scores 40+ | 10.3% | 13.6% |
| 5-year enrolment growth | -2% | -5% |
| ICSEA Average 1000 | 1111 | 1111 |
| ICSEA percentile | 87th | 87th |
| Top SEA quarter | 42% | 42% |
| Bottom SEA quarter | 5% | 4% |
| Students per teacher | 12.2 | 11.6 |
| Teaching staff (FTE) | 96.4 | 80.2 |
| Non-teaching staff (FTE) | 43.5 | 38.9 |
| Language background other than English | 27% | 8% |
| Indigenous students | 0% | 0% |
| Suburb | Heidelberg 3084 | Box Hill 3128 |
| Council area | Banyule | Whitehorse |
| Remoteness | Major Cities | Major Cities |
| Website | www.olmcheidelberg.catholic.edu.au | www.sion.catholic.edu.au |
The verdict
- •Both schools have almost identical Success Index scores (76.8 vs 76.0).
- •Our Lady of Sion College has fewer students per teacher (11.6 vs 12.2).
- •Our Lady of Mercy College is the larger school with 1,175 students compared with 930.
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 Our Lady of Mercy College better than Our Lady of Sion College?
The two schools are very close on the Success Index. Differences in sector, size, year range and distance from home will matter more than the score.
How far apart are Our Lady of Mercy College and Our Lady of Sion College?
About 8.7 km in a straight line, between Heidelberg and Box Hill in Victoria.
Which has the better student-to-teacher ratio?
Our Lady of Mercy College has 12.2 students per full-time-equivalent teacher and Our Lady of Sion College has 11.6.
How do Our Lady of Mercy College and Our Lady of Sion College rank in VIC?
Our Lady of Mercy College is 50th of 348 and Our Lady of Sion College is 63rd of 348 among secondary schools in Victoria on the 2025 Success Index.