Summarizes and critiques research on the role of mathematics content knowledge in the preparation and teaching practice of elementary (K-8) teachers in the United States. Calls for future research to give us longitudinal "videotapes" of teachers' knowledge and how it is developed and used in a variety of contexts. (Author/MM)

Describes a professional development program for secondary school mathematics teachers in which the focus of the program is mathematical definition. The program aimed to develop teachers' subject matter knowledge including knowledge of the substance of mathematics and knowledge about the nature and discourse of mathematics. (Author/MM)

Highlights the issues raised with regard to preservice teacher confidence, attitude and course provision by the decision to expose them to deficits in their content knowledge at the beginning of their training period. (Author/MM)