It is fascinating to listen to middle school students talk about food for plants and animals and how that food is used. Some students describe ideas that are essentially correct. Some comments suggest that students are familiar with the content, but their understanding is incomplete or includes inaccuracies. Finally, some students have little…

The author describes how he used to teach a unit on food webs and ecosystems using actual food webs as models. However, the models used by the author tend to be either too simplistic or too complicated for his students. A few years ago, he solved these problems by making up his own food web, complete with invented plants and animals. The model has…