I did it last year (see sig) and absolutely loved it. It's the kind of course which requires a deep understanding of interconnected concepts rather than rote-learned essays or micro details. Which means that it's great to study because you can do it by discussion or even just by thinking about it
. My study for the HSC consisted solely of making a master set of study notes and then talking about possible essay questions with my friends and family, which was fun.
Don't get me wrong, it's a hard course to get right and you have to learn how to channel your thinking into the kind of responses that they want but it really is like a breath of fresh air next to courses like English. And no, it doesn't scale amazingly but as with all courses if you do well then you reap the rewards.
IIRC the Preliminary course involves things like your personal and social world, adolescence and developmental theories and intercultural communication. The HSC year, if you keep it, involves Social and Cultural Continuity and Change (where you have to do a national case study) and then two other case studies (I did popular culture and belief systems), as well as the PIP.
The PIP is challenging because it's long-term and requires you to work independently but if you pick something you really like (not something that you feel like you have to do) then it's very rewarding. So for people who are starting it, I'd advise you to look at what you're interested in first of all and see whether it could be related to a PIP study.
Basically I'd encourage people to ignore the scaling and choose it based on interest because if you really like it you'll put in the effort required to do well, and then the scaling won't hurt you anyway
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