thanks Loy58- You are correct that the students in 3rd and 4th grade took the other test, MAP-M. There was discussion at our meeting on if our DS should take it or not. I would say that his addition and subtraction facts are pretty solid, but not multiplication or division. For example, when calculating the area of a square, the length of each side was 7, so he said. "oh so that means 7x7... hmm... well I can do it this way, 21+21=42 and that's six 7s, so one more seven is 49." He has strong math reasoning skills, but I don't think that makes up for actually being instructed in the strategies he would need in 4th grade.
He enjoys multi-step problems, but the amount of writing and homework are also good considerations. He's about a year ahead in reading and writing, but there's a big difference between a 2nd grader and a 4th grader's writing. I'll bring up that concern to his teacher.