Open Dynamic Situations of Classroom Use of Digital Technologies: Investigating Teachers' Interventions.

This study addresses teachers' activity when working with digital technologies (DT) in their classrooms. We build upon a model that considers teaching as managing . Within the model, teachers' activity is viewed as diagnosing students' mathematical activity, managing uncertainties due to the characteristics of the situation and decision-making about didactic interventions. The study extends our earlier work and focuses on teachers' interventions in DT-based lessons, as they manage disturbances caused by unexpected difficulties. Our first observation is that there is a substantial change in how teachers diagnose these difficulties compared to paper-and-pencil environments. Notably, they need to make more inferences about the pedagogical support that is provided. Second, we show that in such conditions, rather than facing the single dynamicity of the class as a whole, the teacher has to deal with multiple, open dynamic situations (small groups named mini-classes), which are themselves intertwined in the dynamics of students' interactions with technology. Moreover, even if teachers are able to make reliable inferences concerning an individual student's current difficulties, they must also be able to make inferences about the scope of such difficulties within the class as a whole. We present four case studies that illustrate the diverse approaches that teachers take when managing such open dynamic situations and use them to illustrate the concepts and analytical tools that are introduced.