Good practice encourages contacts between students and faculty.
The most valuable contacts seem to be those that focus on intellectual interests, value issues, or future career concerns. Good practice develops reciprocity and cooperation among students. Ignoring the contributions that students can make to each others' learning is a waste of a valuable resource. Students need opportunities to express their ideas to an audience that matters, and to reflect on the ideas of their peers. We owe our students the opportunity to reach that level of understanding by explaining concepts to their peers.