This paper describes a study in which we investigated relationships between defining mathematical concepts--increasing and decreasing infinite sequences--explaining their meanings and classifying consistently with formal definitions. We explored the effect of defining, explaining or studying a definition on subsequent classification, and the…

Proposes that ability is a concept central to the current practices of mathematics teaching. Argues that the widespread view that mathematics learning is an ordered progression through a hierarchy of knowledge and skills subjects students to "ability stereotyping" and serves as a gross global model. (TW)