In this outdoor, beach activity, learners use tennis balls, water balloons and other simple devices to investigate the movement of waves and currents off a sandy beach. This activity should be done on a gently sloping, unprotected, sandy beach on the outer coast, or the beach of a large lake when there is enough wave action. Learners will notice and collect organisms and remnants of organisms that they find on the beach. They are then given the task of determining how these objects arrived on the beach. Did it have anything to do with the currents, tide, or wind? Learners can also help prepare equipment for the activity, depending the learners' age.