Diamond Harbour School vs Sumner School
A head-to-head comparison of two full primary schools in Canterbury, New Zealand, 6.9 km apart, using official New Zealand 2026 data. The better value in each row is highlighted.
Diamond Harbour School
Diamond Harbour · State full primary · Years 1–8
122 students
Sumner School
Sumner · State full primary · Years 1–8
323 students
| Measure | Diamond Harbour School Diamond Harbour, Canterbury | Sumner School Sumner, Canterbury |
|---|---|---|
| Success Index (NZ) | 65 Top 50% | 75 Top 25% |
| Region rank | #74 of 187 | #35 of 187 |
| National rank | #502 of 1,559 | #275 of 1,559 |
| Sector | State | State |
| Type | Full Primary | Full Primary |
| Year range | Years 1–8 | Years 1–8 |
| Students | 122 | 323 |
| Equity Index (EQI) | 412 | 382 |
| Total roll | 122 | 323 |
| Roll growth (5 yrs) | -4.9% | -17.2% |
| Leavers with NCEA Level 2+ | – | – |
| Leavers with NCEA Level 3+ | – | – |
| Leavers with University Entrance | – | – |
| Māori students | 9% | 7.7% |
| Pacific students | 2.5% | 1.5% |
| International students | 0% | 0.3% |
| suburb or town | Diamond Harbour | Sumner |
| region | Canterbury | Canterbury |
| Website | www.diamondharbour.school.nz | www.sumner.school.nz |
The verdict
- •Sumner School scores higher on the Success Index (NZ) (75.1 vs 64.8).
- •Sumner School does better on equity index (fewer barriers is higher) (382 vs 412).
- •Sumner School does better on roll size (323 vs 122).
- •Diamond Harbour School does better on roll growth (5 years) (-4.9% vs -17.2%).
- •Sumner School is the larger school with 323 students compared with 122.
The Success Index (NZ) 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 Diamond Harbour School better than Sumner School?
On the Success Index (NZ), Sumner School ranks higher (75.1 vs 64.8 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 Diamond Harbour School and Sumner School?
About 6.9 km in a straight line, between Diamond Harbour and Sumner in Canterbury.
Which has the better Equity Index (EQI)?
Diamond Harbour School: 412. Sumner School: 382. Ministry of Education measure of socio-economic barriers faced by students; lower means fewer barriers.
How do Diamond Harbour School and Sumner School rank in Canterbury?
Diamond Harbour School is 74th of 187 and Sumner School is 35th of 187 among full primary schools in Canterbury on the 2026 Success Index (NZ).