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Construct-o-straws

Make a cube out of straws and have a go at this practical challenge.

Matchsticks

Reasoning about the number of matches needed to build squares that share their sides.

Little Boxes

How many different cuboids can you make when you use four CDs or DVDs? How about using five, then six?

Painted Faces

Age 7 to 11
Challenge Level
You could try concentrating on just one face to begin with. Which small cubes on this face will have two of their faces painted?
So where else will there be small cubes with two faces painted?