simo101, dont worry too much. I know you probably have been told this before, but what i do is review the sac thoroughly see where i went wrong then rectify my problems. If your teacher could, ask for the same sac / or maybe another one, and revise again (like it were a real one) and see how you go.
I know im a victim of it as well, but dont get too fussed of the mark, of course it is a reflection about your knowledge on that topic, but if you are able to see where you went wrong and fix your mistakes you should be fine for when exams come. Review and Repeat.
On the note of your ss, its all about ranking, you may have gotten 56%, but this may also be top of the class? think about it this way, a low ranked school will have easier sacs then say a top end private school, at the end of the year when VCAA calculate your SS they will factor this in and moderate accordingly.
good luck
