St Mary's Separate School vs Thousand Islands Secondary School
A head-to-head comparison of two schools in Ontario, Canada, 713 m apart, using official Canadian 2025 data. The better value in each row is highlighted.
St Mary's Separate School
Brockville · Catholic elementary · Grades 7-8
175 students
Thousand Islands Secondary School
Brockville · Public secondary · Grades 9-12
640 students
| Measure | St Mary's Separate School Brockville, Ontario | Thousand Islands Secondary School Brockville, Ontario |
|---|---|---|
| Success Index (Canada) | 38 Lower 50% | 44 Lower 50% |
| Province rank | #2667 of 3,871 | #452 of 766 |
| National rank | #2667 of 3,871 | #452 of 766 |
| Sector | Catholic | Public |
| Type | Elementary | Secondary |
| Year range | Grades 7-8 | Grades 9-12 |
| Students | 175 | 640 |
| Enrolment | 175 | 640 |
| EQAO Grade 3 | – | – |
| EQAO Grade 6 | – | – |
| EQAO Grade 9 maths | – | 46% |
| OSSLT pass rate | – | 89% |
| Low-income households | 10% | 11% |
| Parents without a credential | 5% | 4% |
| First language not English | 0% | 3% |
| Special education | 25% | 38% |
| Identified as gifted | 0% | 1% |
| FSA literacy score | – | – |
| FSA numeracy score | – | – |
| FSA Grade 4 literacy score | – | – |
| FSA Grade 4 numeracy score | – | – |
| FSA Grade 7 literacy score | – | – |
| FSA Grade 7 numeracy score | – | – |
| city or town | Brockville | Brockville |
| province | Ontario | Ontario |
| Website | www.stmarychs.cdsbeo.on.ca | tiss.ucdsb.on.ca/ |
The verdict
- •Thousand Islands Secondary School scores higher on the Success Index (Canada) (43.5 vs 37.5).
- •Thousand Islands Secondary School is the larger school with 640 students compared with 175.
- •St Mary's Separate School is a catholic school while Thousand Islands Secondary School is a public school, so fees and admission rules differ.
The Success Index (Canada) summarises published results and context from official data. It does not measure teaching quality or fit. Methodology.
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Frequently asked questions
Is St Mary's Separate School better than Thousand Islands Secondary School?
On the Success Index (Canada), Thousand Islands Secondary School ranks higher (43.5 vs 37.5 out of 100). The index is built from published results and context data, not from teaching quality or fit, so visit both schools before deciding.
How far apart are St Mary's Separate School and Thousand Islands Secondary School?
About 713 m in a straight line, between Brockville and Brockville in Ontario.
Which has the better Enrolment?
St Mary's Separate School: 175. Thousand Islands Secondary School: 640. Students enrolled in the latest published year.
How do St Mary's Separate School and Thousand Islands Secondary School rank in Ontario?
St Mary's Separate School is 2667th of 3,871 and Thousand Islands Secondary School is 452nd of 766 among elementary schools in Ontario on the 2025 Success Index (Canada).