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## 'Endless Noughts and Crosses' printed from http://nrich.maths.org/

This is a game for two players. You will need a sheet of grid
paper (or rule lines down a sheet of writing paper).

The game is played like the ordinary game of noughts and
crosses, with each player taking turns to mark a square with a
nought or a cross, but does not end with first string of three
noughts or crosses. Keep going until either the grid is full or
both players have had enough! The winner is the player who has the
most strings-of-three. You might find it helpful to use different
colour pens or to keep score as you play.

Playing on such a large grid means that the game is very
unlikely to end in a draw and there is plenty of time to think
about strategies for winning.

Once you have mastered strings-of-three, try a game with
strings-of-four, then strings-of-five, maybe even
strings-of-six!