The purpose of this study was to characterize and compare novice and experienced elementary teachers' pedagogical knowledge and pedagogical content knowledge of three major topics in mathematics: whole number operation, fractions, and geometry. The study participants were 26 preservice elementary teachers and 28 experienced kindergarten through sixth grade teachers. Data were collected via the Survey on Teaching Mathematics, a research-designed instrument that assists in describing pedagogical content knowledge. The results seemed to indicate that experienced teachers possess a greater conceptual understanding of whole number operations than do novice teachers, but that both novice and experienced teachers possess primarily a procedural knowledge of fractions. In addition, the results indicated that both novice and experienced teachers think that a good teacher is one who shows and tells students how to do the work. The findings imply that both novice and experienced teachers need to revisit and extend their own mathematical understandings. They need to explore, identify, and challenge their assumptions about the teacher's role and to develop pedagogical content knowledge. (Contains 11 references.) (Author/ND)