This paper extends and develops theories of mathematical learning to provide a framework for the analysis of classroom video data of students working at a computer in a task aimed at increasing understanding of multiple representations of quadratic functions. Student interactions are coded using novel software tools in the process of analysis, and for the presentation of results. In combination with the theoretical framing these techniques provide a rigorous approach to the analysis of the data. The analysis traces the development of mathematical learning over the course of one lesson and highlights the importance of feedback in the process. Of particular importance is the role of the computer in providing this feedback. (Contains 7 figures.)