OC vs Selective Test: What's the Difference? (NSW)

If you have heard both names thrown around at school pickup and quietly nodded along, you are not alone. The OC test and the Selective test get talked about as if they were the same exam, and they really aren't. They happen two years apart, they lead to two different kinds of placement, and one of them includes a writing task the other doesn't. Once you see how they sit in your child's school journey, the rest stops being confusing.

What each test is actually for

The Opportunity Class (OC) Placement Test is sat by Year 4 students. If your child is placed, they move into an opportunity class for Years 5 and 6 - a class for high-potential students that, in most cases, runs at a different government primary school from their current one. It is still primary school, just a more academically stretching version of it, and it lasts two years.

The Selective High School Placement Test is sat by Year 6 students. A place here means your child starts Year 7 at a selective high school - a separate school they attend right through to Year 12. This is the bigger commitment: it changes which high school your child goes to for six years. (If you are weighing that up, our piece on whether to send your child to a selective school walks through the trade-offs.)

Both tests are run by the NSW Department of Education's Selective High Schools and Opportunity Classes team, both are fully computer-based, and both are held in May. So the machinery looks similar. The difference is when your child sits it and what they win.

The differences that actually matter

Here is the side-by-side. Two rows do most of the work for parents: who sits it (Year 4 vs Year 6) and test sections (three vs four). The rest follows from those.

The headline on sections: the OC test has Reading, Mathematical Reasoning and Thinking Skills, all multiple choice. The Selective test has those same three plus a typed Writing task. On the Department's own figures, the OC test runs roughly 40 minutes for Reading, 40 minutes for Mathematical Reasoning and 30 minutes for Thinking Skills. The Selective test is a little longer and adds a 30-minute Writing section to the mix. The thinking style is the same across both - it is the age of the content, and that extra writing piece, that change.

How places are decided - and what changed in 2025

This is where a lot of older advice online is now wrong. From 2025, NSW primary schools are no longer required to submit school assessment scores for either test, so placement rests on the placement test result itself. The Department also runs an Equity Placement Model that reserves up to 20% of places at each selective school and opportunity class for students from under-represented groups, and is moving co-educational selective schools and OCs toward gender parity in their offers. If you read a guide that still talks about moderated school marks deciding entry, it predates these changes - our rundown of the major changes to the Selective and OC tests from 2025 has the detail.

Which one should my child do?

My honest take after years of this: treat them as two separate decisions, not one. The OC test in Year 4 is lower-stakes - a place is lovely, but missing out costs your child nothing for high school. It can be a useful early read on how your child handles a timed, on-screen test, and the opportunity class itself suits a child who is bored and wants more stretch. The Selective decision in Year 6 is the one that genuinely changes where your child spends high school, so it deserves more thought about fit, travel and temperament, not just test scores.

If your child reads for pleasure and isn't rattled by tests, sitting both is reasonable. If maths worksheets currently end in tears, I would steady the fundamentals first and not pile on two campaigns at once. You know your kid better than any score does.

Whichever path you choose, the preparation rewards the same habits: wide reading, calm timed practice on a computer, and real exposure to Thinking Skills questions, which most children never meet at school. That is exactly what we build into OC Mastery for Year 3-4 students and Selective Mastery for Year 5-6 students - because a child who has only ever done questions in bite-sized chunks tends to freeze when they first see a full paper and a clock.

How the prep differs in practice

For the OC test, the work is building strong Year 4-level reading and maths reasoning and getting comfortable answering on a screen. There is no writing to prepare, which surprises a lot of parents. For the Selective test, you add a typed writing piece - planning quickly, writing to a prompt, and finishing inside 30 minutes - on top of harder, Year 6-level reading and maths. The earlier a child is reading widely and writing regularly, the less of a scramble Year 6 becomes.

For the official format, sample questions and current dates, go straight to the source: the Department's placement test page covers both tests in one place. And if you want our full walk-throughs, see the 2026 OC test guide and the 2026 Selective test guide.

Common questions from parents

If you take one thing away: put both test windows in your calendar now, with their application dates the year before. The families who feel calm in May are almost always the ones who knew the dates in the previous October - not the ones who prepped the hardest in the final fortnight.