Thank you everyone for responding. We had the meeting earlier today. The principal told us within first 5 minutes that they are not accelerating and will discuss how they can differentiate. They had Jo Baoler's book Mathematical mindsets 4th grade that the teacher showed us. But the classroom teacher admitted that her differentiation tasks will be limited by the grade level topics.
Prinicial initially said that it is district's policy, when we asked to see the policy, she mentioned that it is their philosophy and upon asking she told us that there are few kids in the district who are twice accelerated in math but none in her building. Their only reasoning for this was that there are 5 more kids who scored in the 99th percentile in math is his class and one of the kid is in the 250 's so what do they do with that kid. I explained to them that they need to consider his ability not just the achievement score and also see the consistency. It was a bit frustrating. I feel like there is a wiggle room but now they have wasted a whole month. I transferred all the records well in advance before moving but nothing was done. I can get the district's high ability coordinator involved but don't want my son to experience any negativity from the school staff if we go to that extreme. We can do some enrichment at home but not homeschool as he loves the recess, sports, PE and the social part of going to school. I feel like giving up but my husband wants to pursue it further. I am not sure at this point.