I like brilliantcp's idea of being proactive in discussing these situations with kiddos:
Originally Posted by brilliantcp
Fortunately, DD and I had talked several times prior to that incident about how you can tell when someone is really ignorant because they will use sentences with the phrases "girls can't" or "girls don't" or "boys can't" or "boys don't" and she was then allowed to completely ignore whatever they said next as being their own misguided opinion.