Cartesian Divers

From the Centre for Science Education, and with support from Shell Education services, these materials help children to consider questions relating to gases, pressure, floating and sinking. A Cartesian diver is a simple toy that works using the same principles as a submarine. It modifies its buoyancy to make it dive or sink. The diver can be made from simple household objects, but it needs to be carefully assembled. Teacher guidance gives information on the materials required, scientific context and an outline of the activity.