Young surveyors look for patterns in water flow around campus. Using a map of the school (that you will need to create), they mark the direction of the path of water. They also perform calculations for the volume that becomes runoff. The ultimate objective is to consider the best places for setting up a rain garden, which is the focus of the larger unit that this lesson comes from. Note that although the unit is adaptable to all grade levels, this particular component is only for grades four and up.