Honest affirmation will move young people to feel more inclined to respond. One of the reasons youth hold back from conversation or offering their ideas is because their insights at this stage are tightly tied to who they are. They are at the stage of development where they seek to personally own their faith. So as they share in class, give a note or a word of encouragement, citing specific things they said, thus affirming their response. One of the key attributes of an effective learning environment is a positive feeling about the place, the people, and things students say.