I really enjoyed the video clip. And yes there are students that like to raise hand and ask questions and comment. I have found that these students are usually very smart and eagar to get involved and gain most from the class content. Although they do slow you down and the class and keeps bring you back the topics you have covered already. Sometimes I feel that the class gains from it as we get to discuss previously covered topics and referesh everyone's memory. In addition to that I get a feel for how many students retained the information and to what extent as I tend to involve everyone when I am answering the overly curious student.