Cameras need to be placed so that every seat on the bus is within the field of vision. In most cases, that will likely require a minimum of two cameras. The first camera should be aimed at the front entry to view students as they enter and exit the bus. A second a camera should be mounted at the front of the vehicle to allow a clear view down the middle aisle. On larger buses, it may be necessary to mount a third camera halfway down the aisle to fully capture events in the back rows of seats.