A quick survey of physics textbooks shows that many (Knight, Young, and Serway for example) cover estimation, significant digits, precision versus accuracy, and uncertainty in the first chapter. Estimation "Fermi" questions are so useful that there has been a column dedicated to them in "TPT" (Larry Weinstein's "Fermi Questions.") For several years the authors (a college physics professor, a retired algebra teacher, and a fifth-grade teacher) have been playing a game, primarily at home to challenge each other for fun, but also in the classroom as an educational tool. We call the game "The Plus or Minus Game." The game combines estimation with the principle of precision and uncertainty in a competitive and fun way.