You have the Math rit scores. They provide information on what the child is supposed to be ready to learn next. Ask for that information. See if it matches your information, then ask 'what classroom would my child have to sit in to learn what he is ready to learn in Math (not in sitting and waiting skills) and have a few academic peers?'
The SCAT is nice as a confirmation, but I don't think it will help with the school - Those MAP tests should be gold to your situation.
If you feel like you could cry - go cry to the principal - she needs to see it. If you son is suffering emotionally, find a way to share that story with the school. That is what will catch their attention.
Peace,
Grinity
