" The teacher is no longer merely the-one-who-teaches, but one who is himself taught in dialogue with the students, who in turn while being taught also teach."
-Paulo Freire (1921-1997)
It is true that one of the best ways to learn is to teach. It gives us a better understanding of the material from the ground up. If we can take something complicated and distill it down so that someone else can learn it, we are mastering the concept ourselves. In addition, in the role of teacher, we are asked questions - questions we might never have thought of on our own. In finding the answers, we learn more about the concept, and about ourselves. So the students become the teachers as well. We are all teachers, just as we are all students.