Set is a game of visual perception involving a deck of eighty-one unique cards that can be played by people with little or no mathematical background, but the game can also be thought of as a collection of $$3^4$$ objects that can be used to prove things about the game. The class will cover an introduction to modular arithmetic, a proof of why there must be a set given any 21 cards of an 81-card deck, and, assuming time permits, exposure to a few variations of the game and proofs regarding them.