Noughts and crosses
Noughts and Crosses (or Tic Tac Toe as it is sometimes known) is a game for two players.
You will need a piece of paper and something to write with.
How to play:
Decide who will be 'noughts' and who will be 'crosses'. The player who is noughts always draws a nought (or zero). The player who is crosses always draws a cross.
Draw a grid like this between you:
Take it in turns to draw a nought or a cross (depending on which player you are) into one of the nine spaces of the grid. Once a space is filled, it cannot be changed or used again.
The aim of the game is create a line of three noughts (if you are noughts) or a line of three crosses (if you are crosses). The line can be horizontal, vertical or diagonal.
Play several times. Have you any good ways of trying to win?
Bernard says that if you play Noughts and Crosses correctly you never lose, and if your opponent plays correctly you cannot win. Do you agree with Bernard? Why or why not?
Look at all of these games. What do you notice about the strategies they employ?
We suggest tackling them in the order given.