Sasha Wang revisits the van Hiele model of geometric thinking with
Sfard's discursive framework to investigate geometric thinking from a
discourse perspective. The author focuses on describing and analyzing
pre-service teachers' geometric discourse across different van Hiele
levels. The explanatory power of Sfard's framework provides a rich
description of how pre-service teachers think in the context of
quadrilaterals. It also contributes to our understanding of human
thinking that is illustrated through the analysis of geometric discourse
accompanied by vignettes.