My sister keeps calling this 'The Music Man'

There was this time a while ago when my little sister didn't have cable at home, so she would just watch whatever came on network TV and sometimes it was hard to catch the titles of certain programs if you don't catch it from the beginning. She said she watched this movie on TV that she really liked called "The Music Man." She would describe it, but she could never give me more to go off on so I could check it out. That summer, I was watching "Close Encounters of the Third Kind" on TV, and she goes..."That's him, The Music Man!" We finally figured out what the movie is really called. Anyway, I still haven't watched it yet. I'm still waiting for it to come on network TV again.