Learning versus playing. That dichotomy seems natural to people such as my radio host, my debate opponent, my President, my Education Secretary — and maybe you. Learning, according to that almost automatic view, is what children do in school and, maybe, in other adult-directed activities. Playing is, at best, a refreshing break from learning. From that view, summer vacation is just a long recess, perhaps longer than necessary. But here’s an alternative view, which should be obvious but apparently is not: playing is learning.Peter Gray