One of my favorite strategies in teaching a mixed-knowledge-level group (and aren’t they all) is to talk above them, then wait.
This, mind you, is for fundamental concepts, presented in the way I want them understood. For example, last night I spent close to 15 minutes on the functional meaning of 12/8, leading into an understanding of the difference between 12/8 and 6/4 and how hemiola works to tie the two together.
Some of my students grasped this concept on first explanation. Others needed to ask a lot of questions, and maybe still weren’t quite clear when they left. That’s okay. They’ll reach understanding if they desire it, and in the meantime, I’ve made clear that there is more in this world for them to reach for.
The middle of the lesson is chaotic – questions from all sides, good (and mistaken) references to knowledge they already possess. It’s worth it as, one by one, they begin to see the picture I’m painting.
Talk above the knowledge level of your students (at least, on average.) And then wait. Wait for them to understand. Wait for them to ask questions. Wait for them to say, “wait, but…” Answer every question, invite them and wait for them.