Don't know if its too late.. but:
We didnt do this as an assessment, but we did some pracs on projectiles using computer simulations.. sort of hard to prepare yourself for without the software though. Basically the program just shows you a video clip of say, a ball being thrown across a room, and then you go back frame by frame and mark the ball's trajectory and from this the computer draws up all sorts of graphs like acceleration vs displacement or time, or whatever.. then we were just asked stuff like, what was the balls acc. at time t... etc.
What exaxctly have you been told about this assessment, other than its on space and its a prac? So, are you doing it individually? in groups? will you be in your normal classroom? or have they given you a room change so that you'll be in the computer lab etc? will the teacher perform the prac and you just take notes then sit a paper? or will you be given equipment and have to do it yourself? You can prob deduce a fair amount about what the prac will be like if you know the answers to these sort of questions.. and then just study/practice accordingly. Check up what pracs your textbooks have for this topic, at our school that would give you a good indication of what could be expected of you, and then the teacher would just modify it slightly so you didnt know exactly what was required of you beforehand. I guess it depends on how lazy/creative your teacher is as to whether it will be something like everything else you've done or something completely random.
All the best.