I initially sent my kids to the biggest (about 500) school in town assuming that would allow for ability grouping as there were several classes at each level. I found they deliberately split the bright kids over the classes because having bright kids made it easier for the teacher. I bave moved my younger to a smaller school where they placed him in a mixed class as the youngest and are really helping him with learning to manage his emotions. Big should be more flexible but doesn't seem to be.