Sadly, far too many kids are on Ritalin as a means of social control that has nothing to do with the child's well-being, and they get that way from docs who are too eager to prescribe drugs. (A subject which can be tempered by pointing out that if docs don't prescribe drugs, many patients assume they aren't "fixing" anything.)

In addition to checking the medication levels with the current doc and getting more background from the school, I would also seek a 2nd and 3rd medical opinion on the child. It may provide some perspective on the child's condition (or lack thereof.)