I use the concept of mini-lessons in my English Composition course. Each class session is started with a writing prompt. The goal here is to get them in the habit of using and becoming comfortable with the writing process: list, clustering, outline, freewriting, outlining, drafting, revising, etc. It gives them many opportunities to self-evaluate along the way as well. We find out how they feel about criticism as well. Also, we conduct peer reviews. These activities combine to accelerate their growth as writers. The mini-lessons work because the students transition through to higher levels of writing. The writing process has become a habit -- hopefully!
Example: I break up my discussion of the ten comma rules into 10 mini-lessons. You have to convey why what you're talking about is important as well, which is especially important for the adult learner. I started a discussion with a religious instruction class on the topic of the importance of commas by relating 10 biblical verses that resulted in debates over comma use in the Bible. An example is a debate over the comma use in Luke 12:43. The debate revolved around whether the comma should be placed before or after the word "today" in the verse. I related the fact that the bible was written without punctuatiothatifonewasreadingtheoriginalhebrewtextitwouldhavelookedlikethis!!! (You can't imagine how hard it was for me to type that without spaces!).
I tried to hook them on the importance of commas by linking the comma to a topic they were interested in and by breaking the presentation into 10 quick mini-lessons.