Strings and straws are snipped and as many working "fingers" as possible are fitted onto a "wrist" and into a latex glove. The test is - can it be manipulated to pick up one straws, a bundle of straws from a a box, hold a foam ball or a juggling ball for five seconds. As one of our members - a former teacher - said "It's wonderful when you see the moment the penny drops and they get it!" ! The student teams couldn't be assisted except by asking things like - "Will that fit into the glove, have you got enough string to make all of the fingers, look at your own hand, can you see how many joints are in one finger?" and so on.
The challenge gets students thinking about the very real aim of creating a functional hand - an expensive and slow process in the real word, no less complex in a one and a half hour table top session.