“Learning retention rate corresponds directly to personal engagement. In the process of teaching a concept or skill to others, for instance, a person achieves an impressive 90 percent retention of that knowledge. Through the practice of doing, without the additional task of teaching, the retention rate falls somewhat to 75 percent. And the diminishing return continues from being in a discussion group (50 percent), seeing a demonstration (30 percent), an audio-visual presentation (20 percent), and, toward the bottom, reading (10 percent) and hearing a lecture (5 percent).”

This interesting information came from Inform magazine.  A publication of the Institute for Applied Behavioral Science was cited as the source.