Before class, invite a student to prepare a short talk or devotional about a topic or scripture passage. You should give the student clear instructions about what you're looking for in the talk.
For example, don't just assign a student to read Moses 7:18 and give a talk on it. Explain to the student that you are teaching a lesson on unity. Moses 7:18 talks about unity and gives some characteristics of Zion, which was a "unified" city. Ask the student to explain the things s/he learned about unity from the passage in the talk. Explain that s/he is welcome to share personal experiences or find a relevant story or additional scriptures to share.