Make a cube out of straws and have a go at this practical challenge.
Reasoning about the number of matches needed to build squares that share their sides.
How can the same pieces of the tangram make this bowl before and after it was chipped? Use the interactivity to try and work out what is going on!
You may know that opposite faces of a dice add up to $7$, but did you know that there are two different types of dice? Here are two dice, a right-handed one and a left-handed one:
Decide whether the dice below are right-handed or left-handed:
Now try these - they are more difficult.
This problem is taken from the book "Mathematical Activities from Poland" published by ATM.