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Is there a best way to stack cans? What do different supermarkets do? How high can you safely stack the cans?

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Consecutive Numbers

An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.

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Tea Cups

Place the 16 different combinations of cup/saucer in this 4 by 4 arrangement so that no row or column contains more than one cup or saucer of the same colour.

9 Hole Light Golf

Age 5 to 18 Challenge Level:

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Can you convince yourself that it is possible to reach every possible arrangement of lights?

We think this 3x3 version of the game is often strangely harder than the 5x5 version, which can be found here. Why might that be true?