  Mrs. VA, I think trying to get more people involved in the discussions is a good idea. However, knowing what it's like to be one of the ones that is not easily motivated to state my opinion during class, I feel that the best way would be to encourage the other students to try to bring the less responsive ones into the discussion. Having a teacher pinpoint you in the middle of a discussion never seems to work too well. Throughout middle school and other classes many teachers have used that as a technique as a form of punishment for not paying attention, but for our class, many people are paying attention they just don't say as much. Therefore if it's the other students it wont be as much of punishment, but should bring about more of a casual converstion which will allow everyone to feel more comfortable. 
