the truth is if you don't do well of course it will scale you down
if you get band 3/4 for most subject it will automatically scale you down
of course this subject won't scale high like maths
this subject is very helpful and it will overlap if you doing any other subject such as design or business studies
one of the reason students are doing badly in this subject because they don't have enough resources such as additional materials and most importantly computers.
You need to practice a lot in certain areas such as petty cash, invoice etc.
if your teacher can't teach, go to
http://www.hsc.csu.edu.au/ , the site follows the syllables extremely well and basically you can self-taught using that website.
but i'm not sure the site will change in future due to the syllables is changing next year.
anyway i heard this year exam is gonna be hard, my teacher said the exam pattern goes one year is easy, one year is hard and this we getting the hard one
you can tell by looking at the past papers