As others have said, what you do depends in part what you want from the test. When we did it last year it was partly curiosity about how she would do, but it was mostly because she was taking the state tests without ever having to exercise any test taking skills (never had to skip a problem, manage time, etc.). The "prep" I would recommend is not to study any content (especially if you want baseline data to track growth in coming years), but instead to prepare for what above level will feel like. What we did was to print out an 8th grade state test (type in state test, released items) and you'll find plenty. Then I handed her the math section, talked about the strategy of evaluating problems for difficulty and then quickly solving or moving on during the "first pass". I set the timer for 30 minutes and left her be. She got to problem 3 or 4 and stayed with it--trying to figure it out--for at least 15 minutes. Needless to say, she was surprised when the timer went off. I didn't help her with the problems she didn't know, instead I showed her all the problems later in the test that she could have answered correctly if she'd skipped over the one she didn't know. It helped her see the value in that test taking skill and prepared her for the idea that she could and should expect problems that she couldn't work out on the real test.
