The game uses a 3x3 square board. 2 players take turns to play,
either placing a red on an empty square, or changing a red to
orange, or orange to green. The player who forms 3 of 1 colour in a
This game for two players comes from Ghana. However, stones that were marked for this game in the third century AD have been found near Hadrian's Wall in Northern England.
Some puzzles requiring no knowledge of knot theory, just a careful
inspection of the patterns. A glimpse of the classification of
knots and a little about prime knots, crossing numbers and knot
Again, there are several games to choose from.
Find a partner and a 1-6 dice, or preferably a 0-9 dice if you have one. The interactivity in Dice and Spinners can be used to simulate throwing different dice.
Take turns to throw the dice and decide which of your cells to fill.
This can be done in two ways: either fill in each cell as you throw the dice, or collect all your numbers and then decide where to place them.
Each of you draw an addition grid like this:
Throw the dice nine times each until all the cells are full.
There are two possible scoring systems:
You can vary the target to make it easier or more difficult.
Each of you draw a subtraction grid like this:
Throw the dice eight times each until all the cells are full.
Throw the dice five times each until all the cells are full.
Click here for a poster of this problem.