Participation in the classroom has dropped precipitously in recent years. We describe the use of ActiveClass, an application for encouraging in-class participation using personal wireless devices. This system was used in three sections of two different lower division courses in computer programming at UCSD. Using a notion of ecology to develop our method of analysis, these settings provide a rich source of insight into technology-mediated learning and student activity. We find that a broadening of classroom discourse is possible if attention is paid to both political and material forces present in the classroom.