''Doing Proofs'' in geometry classrooms

This chapter discusses the teaching of proof in high school geometry, in search of the features of proof instruction that might account for the observed isolation of proof from geometric sense making. It argues that beyond the surface differences across episodes where proofs are done, a common system of implicit norms regulates the division of labor, the organization of time, and the nature of the exchanges between students and teacher. “Doing proofs” in high school geometry is an example of an instructional situation in the sense that while occasions in which students and teacher produce proofs may be superficially different, those occasions appear to be regulated by a common system of norms. A model of the instructional situation of “doing proofs” in terms of a system of norms regulating what classroom participants do when engaging in proving is helpful to investigate what it might mean to create a different place for proof in geometry classrooms.