Stage: 2 Challenge Level: 
Now play Tic Tac Toe (Noughts and Crosses). If you play correctly you never lose and if your opponent plays correctly you cannot win.
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Look at all of these games. What do you notice about the strategies they employ?
We suggest tackling them in the order given.
Visualising. Working systematically. Compound transformations. Tangram. Interactivities. Practical Activity. Trial and improvement. Generalising. Games. Addition & subtraction.
Published March 2000,March 2004.
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