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Rhombus It

Age 11 to 16
Challenge Level

This game is part of a set of three. We recommend you play this version after having a go at Square It and Parallelogram It.

Rhombus It printable sheet
Printable dotted grid
 

This game can be played against a friend or against the computer.

Players take it in turns to click on a dot on the grid - the first player will place blue triangles and the second player will place pink squares.

The winner is the first to have chosen four dots that can be joined to form a rhombus.

Rhombuses can be anywhere and any size.

Clicking on the purple settings cog allows you to select the size of the grid, who the players are, and who goes first.

Once you've played a few times against a friend, you might like to discuss your strategies, and then test them by playing against the computer.

Can you find a winning strategy?

If you are not using the interactive game, you may like to print off some dotty paper.