This article is concerned with "commonsense science knowledge", the informally gained knowledge of the natural world that students possess prior to formal instruction in a scientific discipline. Although commonsense science has been the focus of substantial study for more than two decades, there are still profound disagreements about its nature…

Outlines a model of mathematical understanding as a whole, dynamic, nonlinear, recursive growing process, entailing "folding back" for the reconstruction of inner level knowing. Presents examples from seventh graders' work. Discusses teacher awareness of student level of understanding, and implications for development of mathematics…

This paper takes the position that logical knowledge is distinct from conceptual and procedural knowledge and can make a unique contribution to the understanding of knowledge acquisition. This view of logical knowledge departs from the traditional Piagetian view of stages and the overriding view of logic as the sole means of constructing new…