Field experiments are at the core of ecology, yet rarely find their way into education, probably due to a combination of technical challenges and risks associated with fieldwork. This may compromise student education and perception of the subject, making interesting, readily manageable experiments extremely important. We describe how the daily cycle of nocturnal mass movements by river invertebrates ("drift") can meet these challenges. The observation of this daily cycle, and simple manipulations using light (to test hypotheses about the triggers for drift) and fine sand (simulating degradation of stream habitats), requires minimal specialist equipment or expertise, yet affords numerous practical benefits and captures student interest through the novel fieldwork. Invertebrate drift illustrates numerous biological principles through investigations adjusted to suit different educational levels. (Contains 1 figure and 1 table.)