Isn't MAP out of level? If it is, and there is a norms chart somewhere, you can look at his raw score and figure out what the grade equivalent is...for instance would the average 8th grader have the same score, the average 10th grader? The average 12th grader? The 99th percentile information can be pretty useless because you don't how far off grade level he is just based on that. DS's teacher told me 99th percentile but we didn't know if he was scoring 2 grade levels ahead, more than 2, or what. It turns out his score (in second grade) is what the average 9th-10th grader scores. It doesn't mean we would accelerate him to 9th grade. But it was more helpful info than just knowing 99th percentile for second grade. The test might tell you a grade equivalent if you have a report. If you have raw scores for math, you could see if you can find it online....some sort of norms chart, listing various percentiles for each grade, like 25th, 50th, 75th, etc.
Also, one more thing about the WISC. It's just one test and it's measuring just certain aspects of ability and gives you a general idea of his cognitive ability. I would take it with a grain of salt.
