Background: People misperceive accumulation processes. Take for example the case of people becoming more drunk than intended. Such misperceptions can lead to high costs that in some cases may be fatal. We ask: Could interactive learning environments (ILE) using water analogies help people understand accumulation processes. Method: High school students participated in a laboratory experiment. Some of them interacted with a funnel simulator in order to learn about accumulation processes. In a two by two full factorial design where some subjects could see the level of water in the funnel...