Most movie theaters encourage quiet, but not when you’re at a musical sing-along at the Castro Theatre.It’s in the dark and you’re part of a crowd, so it’s pretty anonymous singing along to songs from "Beauty and the Beast, The Sound of Music or Grease. It doesn’t matter how old you are and you don’t have to climb every mountain to get there. Some people just love movies and singing.Who doesn’t want to sing along with a hundred other people to their favorite disney classics?