Arched bridge
Build a bridge and test to see whether it can bear your weight. The challenge can also be taken by a group. How many can the bridge hold? How can it be so stable?
Have you ever wondered why old churches and stone arches don’t fall down? Each individual stone is pulled downwards by gravity, but they are supported by an upwards force exerted by the neighbouring stones. If someone stands on the stones of an arched bridge, the upwards force increases, and thus such bridges are stable.
