I'm going to be honest. You can go to whatever school you want no matter the ranking and still do well. But you need to overcome the mental barrier of over confidence that will affect how much hard work you do and how smart you think you are
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When I was in Year 7 in QLD I thought I was an absolute genius at maths. Almost straight A+ for every exam. It showed in my personality. I thought I was better than everyone. I wasn't in a smart class. I wasn't in an academic school. Then when I moved to a NSW selective school for year 8 - even though it wasn't necessarily ranked that well - everything was more difficult. There were more smart kids. Higher expectations. It humbled me.
If you go to a really poor school and do relatively well to your class mates there you have to be aware of it. That dux of your grade with an ATAR of 80, well there are kids consistently getting 99.95s at James Ruse. For students at James Ruse, there's always going to be kids smarter than you in other states, countries and maybe even lower tiered schools. You need to prevent over confidence and get a real view of the situation. You did objectively super well to the state? Congratulations! You should be proud of that. But you must always remember that there's always a bigger fish. There's always someone better.
So don't get too confidant that you don't even try your hardest. Don't be full of so much hubris you immediately shun everyone around you. As it was once famously said, every man is your better in some way. By learning this you could work hard enough to eventually become one of those bigger fish (and you probably already are to many people in the state). So keep up the hard work!
Sorry for making this so dramatic. I genuinely think this could help people. I'm glad I had the experience so young. I get this probably doesn't even match what the thread was talking about but I think it needed to be said.
Honestly, I wish the best of luck to everyone. HSC will be over! ... eventually