Lectures from model teachers are recorded on video and are then physically distributed via DVD to schools that typically lack well-trained instructors (as well as Internet connections). While the lectures are being played on a monitor (which is often powered by a battery, since many participating schools also lack reliable electricity), a “mediator,” who could be a local teacher or simply a bright student, periodically pauses the video and encourages engagement among the students by asking questions or initiating discussions about the material they are watching.