Regarding the WISC, it has four subtests and really isn't something that you are supposed to prepare for although I imagine that it feels pretty high stakes in your situation. We weren't in that spot so much in that dd had taken the WISC two years prior to her skip so we weren't waiting to see if the IQ scores would rule her out. Essentially, the WISC will look at your dc's verbal reasoning abilities (verbal comprehension index), visual spatial and abstract reasoning abilities (perceptual reasoning index), short term auditory memory (working memory index), and speed (processing speed index).
Oh, he's certainly not prepared in any way and because he's never been given an IQ test, we have no idea what to expect. We know he's been in the gifted program since first grade, but you know that doesn't necessarily mean high IQ, and really, the fact that he scored so high on the above-level test was a bit of a surprise. We were the ones who looked into subject acceleration not the school. I think they were content to have an essentially straight A kid who never got in trouble to carry on as usual.
