Well, im not sure that the UAI is partyly to do with your school, but i know that some schools do better than others because they have different teaching styles, teachers, and levels of student motivation.
For example, my public school does very well in the state, where as our neihboring public schools don't. I think its mostly to do with the entire student body work ethic, aswell as the teachers. I know many people that go to my niehboring public schools, the majority don't seem as interested in competing for the highest mark in thier grade, and don't seem to care that the HSC will be based on rank according to the state, at least compared to my school friends.
Now i may be mistaken, but from personal experience it seems to me that its all to do with how serious your peers take competition.
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