No, I'd wait at least a year, UNLESS something comes up that makes it more urgent. If your son starts showing "symptoms" of academic frustration (regularly resists going to school, gets in trouble at school in ways he doesn't at home (talks back to teachers, fights, etc.), openly and regularly mentions academic boredom or lack of challenge, etc.) then you would want to address this FIRST with the teacher and administrators. Out-of-level testing (give a second or third grade math test, reading higher level material, etc.) is regularly used with high-level students, so consider asking for this. If this doesn't get any results, THEN I would consider a retest. Even then with the numbers to support you, you might still not get results from the school. Most of all, try to remain calm and civil when discussing this. Making administrators mad never helps.