And on a more pragmatic note, unless they're giving the grade 2-5 MAP to second graders (which is, of course, possible), then he is not going to see any academic contents above 3rd grade or so, anyway, which, from the sound of it, he has already (or nearly) surpassed. In that case, it is the soft skills even more so that will be the difference between 95 and 98th %ile, since it will be pacing, attention, and self-monitoring that matter. Regardless of his performance on this instrument. at this one moment in time, it may be to his benefit to investigate the whole range of supports for academically advanced students. There may be multiple entry points to different tiers of supports, and instructional challenge in some subjects may be more important to him than in others.
Even if they do give the 2-5 level of MAP (which actually makes some sense for the population under consideration for GT programming), the substantive differences between topics he would have been exposed to if offered higher level instruction earlier and those in the differentiated first grade classroom are relatively smaller. Between first and second grade, you go from learning to read to learning to read more, and from adding and subtracting to 20, to adding and subtracting to 100. Not a huge leap on either score for a high-cognitive learner without other challenges. It sounds like the achievement criteria are from MAP administered throughout grade 2, so it's unlikely that math above single-digit multiplication would play much of a role.
And I am definitely not a proponent of prepping, beyond a passing familiarity with the format of the test, such as schools typically do in the weeks prior to testing. Definitely no prepping for the CogAT, or any cognitive or aptitude test. It's hardly a measure of the student's progress or response to classroom instruction otherwise.
