I dont think your rank in the school means JACK.
You could be tops at the subject and get a teacher who marks u really hard. The go into the HSC and blitz it.
Or you could get top rank at your school cause your teacher is an easy marker in the trial. Then go into the HSC and get totally blown away as to how hard it is.
You school shouldn't mark you on your work you should only get a competent result. No high, medium, low competent just competent. No marks. The your teacher should give you a report based on knowledge skills and attitude.