How to Play Sim
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We have another fun maths game to share with you today. Sim is a pen & paper game for two players. It's named after cryptographer and mathematician Gustavus Simmons, who first introduced the game in 1969.
You Will Need
- 2 players
- pens in two different colours
- some paper
Set-up
Draw six points (in any colour) on your piece of paper, arranged to form a hexagon. We also suggest adding some pencil lines connecting all the points with each other, as a guide for children as it shows them all the possible moves they can make. It should look something like this:
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Alternatively, you can also download our Sim game activity sheet, which already has hexagon templates marked out on it. There are two versions, one has four hexagons to a page, the other has one single large hexagon.
In a classroom setting, teachers can use these in document pockets with wipeable pens, to make them reusable.
How to Play
Players take it in turns to connect two out points of the hexagon grid with a line in their colour. So in this example, green has gone first, and then purple.
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The aim is to avoid forming a triangle where all sides are in your colour. However, only triangles that use three of the outer points of the hexagon count. For example, here green has formed an internal triangle, but it only uses one of the outer points so it doesn't count as a loss.
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Game play continues until one player has no choice but to draw a line that will complete a triangle in their colour. They lose the game, and the other player wins.
In this example, purple has ended up in a no win situation. There are two possible lines left that the purple player could draw, but both of them will lead to a loss.
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Here you can see what happens if the purple player opts for one of the two possible lines - they form a triangle and lose the game.
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Drawing in the other possible line, even creates two purple triangles at once! They need to decide on one of the two options, but either way green wins.
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Maths skills involved: shape recognition, spatial reasoning, logical deduction
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