I was curious about how your son feels about not being selected for the advanced math class on the basis of his test score. The big drop makes me think there's some kind of motivation issue. If he wanted to do the avanced math class it may help to point out the connection to "showing what you know" on the test. If that's the case, I'd ask the school if he could retest because the results were more a reflection of his motivation than his readiness for advanced math. Here's some information on preparing for the ITBS: http://www.education.uiowa.edu/itp/itbs/itbs_use_prep.aspx