Researchers and practitioners alike express concerns about the conceptual difficulties associated with the concepts of momentum and kinetic energy currently taught in school physics. This article presents an in-depth analysis of the treatment given to them in 44 published textbooks written for UK secondary school certificate courses. This is set…

Discussed is the idea that models should be taught by emphasizing limitations rather than focusing on their generality. Two examples of gas behavior models are included--the kinetic and static models. (KR)

Activities involving concave rubber disks are utilized to illustrate the scientific principles of kinetic and potential energy. Provides teacher instructions and questions related to the activity. (MDH)

Discusses the mechanism and the change of pH during the reaction. Notes that a dramatic rise in pH occurs when the reaction nears completion. Evaluates theories by other authors. (MVL)

Presented is an analogy that can be used to explain the particle theory of matter. The three phases of matter are represented by preschoolers, yuppies, and senior citizens. The value of using analogies is discussed. (KR)