Children’s conceptions of air pressure: exploring the nature of conceptual change

Children’s responses to a series of air pressure activities were tracked in detail during group discussion and interview, and again in interview six months later. Results for different age cohorts have yielded insights into age-related knowledge components framing children’s conceptions of air pressure phenomena. Case studies of individuals have been constructed to explore the way conceptions change over time, and the difficulties presented by the concept of atmospheric pressure. These are used to evaluate different structural theories of conceptual change. The findings point to the complexity of children’s conceptions, the stability and extension over time of productive conceptions, and the critical role of contextual features of phenomena in the conceptual change process. Although structural aspects of changes in concepts related to air pressure are identified, the difficulty of accessing the atmospheric pressure conception is argued to have more to do with presupposition based in perceptual features of air, and with difficulties associated with the application to particular phenomena.