We investigated how two didactical tools assist high school students in constructing knowledge about convergence and limits. The first tool is manual plotting of the terms of selected sequences, and the second, a technological applet. Student pairs worked in an interview setting on an activity designed for the purpose of this research. The…

This case study deals with a solitary learner's process of mathematical justification during her investigation of bifurcation points in dynamic systems. Her motivation to justify the bifurcation points drove the learning process. Methodologically, our analysis used the nested epistemic actions model for abstraction in context. In previous work, we…

A model for processes of abstraction, based on epistemic actions, has been proposed elsewhere. Here we apply this model to processes in which groups of individual students construct shared knowledge and consolidate it. The data emphasizes the interactive flow of knowledge from one student to the others in the group, until they reach a shared…