Resumen

The purpose of this paper is to present pre-service high school mathematics teachers’ objectual beliefs about the use of Geometer's Sketchpad (GSP) for teaching geometric transformations (GTs). The participants of the study were two senior undergraduate pre-service high school mathematics teachers at a public university in the United States of America. The study comprised a series of ten task-based interviews, five with each participant. I conceptualized radical constructivist grounded theory (RCGT) with five assumptions to guide the research process outlining the relationship between the researcher and participants, as well as emergent process of data construction, analysis, and interpretation. The results include three in vivo categories concerning GSP as an object of teaching GTs. The categories were – interface between algebra and geometry, the semantics of GTs with GSP, and syntactic of GTs with GSP. I addressed pedagogical implications of these categories at the end.