The short answer: the Opportunity Class (OC) test is sat in Year 4 for entry into a Year 5 OC placement, while the Selective High School test is sat in Year 6 for entry into Year 7. They are two separate NSW Department of Education placement tests, taken two years apart, with different section structures. If you are weighing "oc vs selective" for your child, the decision usually comes down to your child's current year level and whether you want a placement now or in a couple of years' time.
The core difference: when the test is sat
The OC test is for students currently in Year 4. A successful placement means your child moves into an Opportunity Class for Year 5 and Year 6 — a two-year academically selective stream inside a primary school.
The Selective test is for students currently in Year 6. A successful placement means your child starts at a selective high school in Year 7. This is the pathway most families think of when they hear "selective", and it covers full and partially selective high schools across NSW.
Because the tests are two years apart, they are not an either/or choice made at the same time. A Year 4 family looks at OC now; a Year 6 family looks at Selective now.
Section-by-section comparison
The tests share a family resemblance — both are computer-based multiple-choice assessments drawn from the NSW curriculum — but the Selective test is longer and adds a writing task.
The OC test has three sections, all multiple-choice and computer-based:
- Reading — 40 minutes
- Mathematical Reasoning — 40 minutes
- Thinking Skills — 30 minutes
Content is drawn from the NSW curriculum up to Year 4, which matters when you plan revision: you are consolidating what a strong Year 4 student already meets in class, not teaching ahead.
The Selective test has four sections:
- Reading — 45 minutes, around 17 questions producing roughly 38 answers (multiple parts per passage)
- Mathematical Reasoning — 40 minutes, 35 questions
- Thinking Skills — 40 minutes, 40 questions
- Writing — 30 minutes, typed on the computer
The Selective test is also computer-based and sat at a designated test centre. No calculator and no dictionary are permitted.
Writing vs no writing
This is the single biggest structural difference. The OC test has no writing component — all three sections are multiple-choice. The Selective test adds a 30-minute typed Writing task as a fourth section.
Practically, that means a Year 6 family preparing for Selective needs to build typed writing stamina and practise composing under time pressure, whereas a Year 4 family preparing for OC can focus entirely on multiple-choice technique across reading, maths and thinking skills.
Format at a glance
Both tests are online and multiple-choice at their core. The differences that affect preparation are:
- Year level: OC in Year 4, Selective in Year 6.
- Entry year: OC into Year 5; Selective into Year 7.
- Sections: OC has three (Reading, Mathematical Reasoning, Thinking Skills); Selective has four (adds Writing).
- Total question load: Selective carries more questions per section and a longer Reading paper.
- Rules: Selective specifies no calculator and no dictionary; treat OC the same way when you practise so there are no surprises.
Which should we target?
Target the test that matches your child's current year. If your child is in Year 4 this year, the OC test is your window — it will not come around again, since OC entry is Year 5 only. If your child is in Year 6, focus on the Selective test for Year 7 entry.
A helpful way to think about it: OC is an earlier, three-section checkpoint; Selective is the later, four-section test that includes writing. Neither result is a published cutoff you can look up — the NSW Department of Education stopped publishing official minimum entry scores after 2021, so treat any "cutoff" figure you see online as an estimate, not an official mark.
Can a child do both?
Yes. The two tests happen at different stages, so a child can sit OC first in Year 4 and then sit the Selective test in Year 6 — whether or not they gained an OC placement. Sitting OC is not a prerequisite for Selective, and an OC placement does not carry over; every family reapplies for Selective in Year 6 through the same process.
Doing both has a real advantage: the OC test in Year 4 is genuine, low-stakes exposure to the online multiple-choice format your child will meet again in Year 6, which can take the edge off test-day nerves for Selective.
How to prepare
Both tests reward the same habits: timed practice in the real online format, section-by-section review of mistakes, and steady exposure to Thinking Skills question types that are not explicitly taught in class.
- For Year 4 students, work through full-length OC practice tests to build multiple-choice pacing across Reading, Mathematical Reasoning and Thinking Skills.
- For Year 6 students, use Selective practice tests and, crucially, practise the typed Writing task under a 30-minute limit so the fourth section does not become a scramble.
- Sit at least a few practice sessions on a computer, without a calculator or dictionary, so the test-centre conditions feel familiar.
- Both tests use the same online application run by the NSW Department of Education: applications open in Term 4 and close in February. Diarise those windows early — a missed application is the most avoidable reason a strong candidate misses out.
If you are still deciding between the two, remember it is rarely a real choice: your child's year level decides it. Prepare for the test in front of you now, and if your Year 4 child sits OC, you have simply given them a head start on the format they will meet again for Selective.
Last verified: July 2026. Test format from the NSW Department of Education.