Developing concepts, modeling, and solving problems form the core of essential learning about addition and subtraction. That educators may make the task more difficult than necessary is the thrust of several recent studies. Highlights from these studies (with suggestions for instruction) are presented. (JN)

Most of the research on mathematical and scientific thinking has been concerned with uncovering knowledge structures and reasoning processes in people of different levels of competence. How these structures and processes are acquired has only recently become a major concern. Thus, some of the major research on mathematical and scientific thinking…

In connection with the formative evaluation of the Developing Mathematical Processes (DMP) curriculum, interviews were conducted with teachers in grades 1-3 at the beginning of the school year and after concluding each of the 10 topics on addition and subtraction. The topics had been especially prepared for a classroom observational study. The…