It's been a few quite a few years since OP posted, but I'll provide a reply as a
NSW HSC Investigating Science student for future viewers.
i) Will studying it with another science help me with that science or vice versa?
The Investigating Science course
has helped me with other science subjects. Not content such as physics formulas, or researching the Doppler effect, but particularly the skills I.S teaches is something I often apply to my other courses. I've noticed in my other science courses, most students would be struggling with revision of science skills. Unlike them, I'd be handling exam questions like a champ because of the skills taught Investigating Science.
Investigating Science is pretty much an all-rounder science subject. It's pretty general and simple in terms of the content being taught (refraction of light - Physics, The Greenhouse Effect - Earth and Environmental Sciences, etc). However, my biggest takeaway from Investigating Science is learning how to analyse and interpret data, evaluate ethical issues surrounding subjects such as nuclear energy, organ transplants and organ donation, and studying how to conduct valid and reliable investigations. In my opinion, if you're going into a field of science requiring research, Investigating Science is one of, if not the BEST subject you can do to benefit that career. There's a reason why there's a compulsory 60* hours of depth studies
ii) Will I have enough resources (and what will be expected of me)?
I had to buy an Investigating Science in Focus Year 11. Did I use it a lot? Not really. My teacher provided samples of the textbook in a pdf format during the lesson for those who didn't have the textbook, alongside other resources such as articles, scientific journals, etc based on what we were studying that day. I didn't bother buying the Year 12 textbook, and for good reason because I can count the number of times we did a lesson based on the Year 12 textbook on one hand. I had a pretty relaxed teacher though, so take my words with a grain of salt. Judge how much your textbook is used in Year 11, and how often the teacher provides resources, and make a judgement from there for Year 12.
Although the syllabus is pretty easy, there is a lot of content. I would expect many resources throughout stage 6 based on the large amounts of topics you're covering. You'd be expected to bring a textbook unless the teacher says otherwise, or if the teacher is someone who provides the textbook (like mine lol).
iii) Will it scale well (i.e. will intelligent kids do this subject)?
I'll be honest. The scaling is absolute crap.
Students often take the subject to bludge. My tiny class of ten students is composed of rowdy teens. Although I have peers who want to learn, it's a pretty general group of kids who don't put in much effort.
This year, my class went on an excursion to an ANSTO facility, and we had to group with another school (with a class even smaller!). Lo and behold, the other class was similar to that of mine. I distinctly remember one kid who genuinely seemed interested in what was being taught, but he was the only one that stood out to me from his classmates mucking around. That sight pretty much solidified the idea that Investigating Science wasn't the best subject to choose for good scaling in general. If you want a great class ranking, choose Investigating Science and put in some effort. That would shoot you right up.
I can't say that every I.S class is made up of 'dumb' kids, but based on my experiences, I haven't seen many of the "intelligent" kids choose the subject. Which is honestly quite saddening considering the subject is so useful for everyday life!
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All-in-all,
I recommend I.S if you're genuinely interested in a career in Science, and the skills science teaches. It was by far one of my favourite subjects, and it is actually because of I.S that I want to pursue a career in scientific research through a BSc degree, then move up to a PhD
I.S teaches individuals how to practise scientific processes and apply those processes to investigate relevant community, personal, and global scientific issues. Want to buy a product? How do you know it's advertisements aren't false, and how are you going to find out if that particular company's taking advantage of you as a consumer? Ever wonder why the sound of a train is higher in pitch coming towards you, and receding in pitch moving away? The subject is great to apply to real world situations if you want to be an informed individual
Although the scaling isn't the greatest, if you do well in stage 6, you could use those grades for early entry into a university science course, should you choose to do an ATAR pathway. Lucky for me, some of the loud kids in my class are doing non-ATAR (which is probably why they chose this subject to bludge).
Anyway, good luck to anyone completing their subject selection, future Year 12 students, and current Year 12 students undertaking their HSCs in a few weeks! I'm not too religious, but since I come from a Catholic school, God Bless