I think engagement is less about the content of the course and more strongly impacted by the relationship of the student and the instructor.
For myself, Intrusive leadership works. I try find a common bond with each student. Once they see that I am approachable, the level of engagement always increases.
Often I find that thte reclusive students either fear failure or have lack of confidence in their ability to succeed. Students are people as well. Many have been told they could not succeed and were not good enough by many people in multiple facets of their lives. Once you build them up, they will almost teach your class for you. Every environment and audience is different as well.
Know your students!!!!!
