Use Those that Know
Young gifted children are intensely curious, produce a constant stream of questions, learn quickly remember easily, and think about the world differently than their peers. You may have a student in mind that seems to know all of the answers in your class and is always actively participating.
Utilizing this amazing resource in your classroom to jumpstart discussions can be a great technique to use in your classes. Make sure that these students are being used as a starting point for discussion and are not being used for the entire discussion. The latter can lead to other students being discouraged to participate, or becoming complacent with their lack of participation.