AP Statistics isn't too terribly difficult if he's already in Precalculus. (He should understand logarithms, but that's as hard as the math gets - it's mostly just algebra.) Computer Science I've not seen myself, but I imagine it's manageable...
The reason for not putting the AP designation on the transcript is likely that they don't have a teacher in the middle school with an approved syllabus. That isn't necessarily a bad thing -- it does show that they're being honest (when a lot of places might not be if they thought they could get away with it), although it's really not that hard for them to get a syllabus approved, especially with this much lead time. It does mean that no one is going to consider it AP until he takes the exam, but it seems like a small risk.
Which class is he more interested in?
