This classroom demonstration illustrates the amount of water stored in various parts of the Earth system in a straightforward manner. Students estimate the proportions of water in the oceans, icecaps and glaciers, groundwater, freshwater lakes, inland seas, soil moisture, atmosphere, and rivers. Then they fill beakers with the actual proportion and discuss what elements of the activity were surprising to them. Information on flash floods and flood preparedness and safety are included.

This learning activity takes approximately 20 min.