I teach part time and I'm aware that most of what I say in the classroom is forgotten. This is a good thing, because much of what I say is biased, lacking a factual basis, and eventually obsolete. The assignments I come up with probably benefit me more than the students, but only if I make an effort to revise them on a regular basis.
In a few hundred years most education will be provided by sophisticated computer algorithms. I think there will still be a human component to learning, but teachers will have more fluid responsibilities and will be managed in large part by the AI systems. Students will spend more time learning how to formulate questions than regurgitate answers. Most answers will be provided by the computer network.