Reflection is a powerful tool for helping pre teens and teens learn. It works with younger children too, but their pool of knowledge is smaller.
Recently I have had a chance to teach classes of 12- 14 year olds and other classes of 15-17 year olds using a method that is centered around questions to start discussions. This method uses lots of backup material in case the discussion doesn’t pan out as expected, or in case they haven’t considered this before. It also drops the idea of trying to teach it all, so if a discussion arises where they are engaged, you can keep it going and expand on that.
They seem more interested in opinions from their peers and listen when a peer speaks and tells of an experience where a particular principle applied in their life.
The questions are intentionally open ended, for example, “How can…?”
Pausing to let them think gives them time to formulate their thoughts.