The document camera has the potential to be more than just a digital overhead projector. Not many people use the camera on the document camera for other than viewing something they are writing on. Having the ability to record the video coming in from the camera can help in the explanation of any topic. Ideas can range from recording an experiment or dissection in a science class, recording students speaking or acting in class, or just helping to record video of the teacher explaining how to organize or construct something.
(Directions are specific to the Elmo brand of document cameras that we use at our school.)