Tic-tac-toe (also known as noughts and crosses or Xs and Os). Tic-tac-toe is a fun game that you can play any time and anywhere as long as you have a piece of paper, a pencil, and an opponent. Tic-tac-toe is a zero sum game, which means that if both players are playing their best, that neither player will win. However, if you learn how to play tic-tac-toe and master some simple strategies, then you'll be able to not only play, but to win the majority of the time. The player who succeeds in placing three of their marks in a horizontal, vertical, or diagonal row wins the game.
Tic-tac-toe like pedagogical tool
Because of the simplicity of tic-tac-toe, it is often used as a pedagogical tool for teaching the concepts of good sportsmanship and the branch of artificial intelligence that deals with the searching of game trees.
Tic-tac-toe helps in making choices
The ability to predict possible events and consequences helps in making choices. Playing games and using strategies to win are ways that we learn to gather data and make predictions. We say to ourselves, "If I move here and then she moves here, then I can do this or that". These reflective strategies players use during a game like chess or checkers, where strategy is the key, are ways to develop this kind of mathematical thinking. State your thinking strategy out loud to help others develop theirs.