Yes, scaling is important in the sense that it is used as part of calculating an ATAR. Essentially, an overall HSC mark in a subject consists of two marks, the average of which produces the overall HSC mark. They are the Assessment Mark and the Examination Mark. The Assessment Mark is the mark that reflects your internal performance in a subject, while the Examination Mark is your HSC exam mark in the subject. The Assessment Mark is subject to the moderation process. Prior to scaling, the average of a moderated Assessment Mark and a raw Examination Mark (raw mark meaning the mark that was awarded without any adjustments) is determined, resulting in a raw HSC mark. This mark is different than the overall HSC mark that you receive as part of your HSC results, the latter being subject to alignment, which has no effect on your ATAR. Subsequently, scaling is applied to the raw HSC mark, resulting in a scaled HSC mark. This is applied across your subjects and goes into determination of your ATAR.
This covers the technical significance of scaling. However, when considered in relation to subject selection, scaling becomes less important, as you are encouraged to maintain the subject combination that would allow you to ensure favourable performance as well as the greatest alignment with your study interests. The better your performance across your subjects, the less significant the effect of scaling.
In terms of the school that you attend, your school rank itself does not matter, although it is indicative of an element that does matter, which is cohort strength. The moderation process mentioned earlier uses your internal rank relative to your cohort in a particular subject as well as your cohort's HSC exam performance in that subject to determine your Assessment Mark for the subject. Generally speaking, the higher your rank, the higher your Assessment Mark is likely to be. Where cohort strength matters is in determining the approximate that you would need in a particular subject that would be consistent with a favourable Assessment Mark. A lower-ranked school is likely to have less academically capable students. As such, a favourable Assessment Mark will likely require you to place among the top students in the cohort. On the other hand, a higher-ranked school is likely to have more academically capable students. Consequently, the same standard of performance in terms of the Assessment Mark can likely be achieved with a lower rank.
I hope this helps!
