Yeh i did hsc geography. You don't really need any of the prelim stuff for the hsc year, but it's nice to be able to throw a couple of interesting concepts/terms into your essays, so just remember some of the core concepts. The trick to doing well in the hsc year is finding interesting statistics/examples that aren't in the textbook (which all the of the state uses). Luckily my teacher did much of this research, but all you really need is a few interesting points for each topic, and they tend to overlap each other anyway. Also, don't bother with the Macquarie Study book haha. It's about a decade out-of-date and I barely touched it all year.