deteriorate if it does not eat. So they understand some of the distinctive processes that are essential to digestion.
Children are also able to recognize particular aspects of or patterns related to living things: that they have an underlying nature and that they are embedded in an ordered system of groups and categories. Indeed, some aspects of children’s beliefs about biology are common across cultures, suggesting that ways of organizing the living world are deeply embedded in human thinking.
With opportunities such as the “Biodiversity in a City Schoolyard” course of study, children’s ideas about the living world undergo a dramatic change during elementary school. They move from seeing plants and animals as special because they possess a “vital force” to seeing them as animated by metabolic activities. They are able to explore, map, and model habitats and ecosystems. In the process, their conceptual understanding of living things undergoes significant changes: they begin to see interconnections among living things in a dynamic system.
Even though the children were young and many spoke English as a second language, much of what the students in Mr. Walker’s and Ms. Rivera’s classes were doing involved generating scientific data. They mapped the schoolyard and developed systematic ways of sampling the number and kind of plants and animals. They collected samples of plants and insects, took careful measurements, and plotted the kind and density of different plant and animal species. They drew careful pictures of stems, leaves, and buds and often cut them open to explore their insides. They also brought specimens inside and carried out sustainability studies of plants in jars, with different kinds of soil, food and sunlight. They created a laboratory to examine the life cycle of butterflies from the caterpillars they found on leaves. They recorded these changes