Bill Quick introduces us to his pocket knife, an impressive little slicer, and down in the comments you’ll find this exchange:
Denny: When I was growing up most of us boys carried pocket knives and we carried them to school.
Bill: Of course. How else can you play mumblety-peg during recess?
Indeed. In my little corner of the world, we played a single variation more or less in reverse: the idea was to keep your footing as long as possible as the knives got farther and farther apart, until eventually one of you did a very clumsy split. (During my, um, prep years, this was one of two Contests of Choice, the other being gin rummy.)
You might be able to get away with playing gin at recess today, but God forbid anyone should spot you with an actual knife. Even if it won’t cut through I Can’t Believe It’s Not Butter! at high noon in the Mojave, you’re out the door.