One of the keys to making IBL work is to make sure that students really engage with the topic. There are lots of ways to do this, but I will focus on two ways to get a whole class discussion going. The first of these ways is to use question starters. I have done this in two ways. In the first case, I simply write a question on each of three or four index cards, and distribute them around the classroom while another student is presenting a solution. The index cards have a single question type, such as, "How did you know where to start?" "Could you explain how you went from ... to ...?" "Can you explain what the question is asking?" "Was this the first thing you tried?" The students are told that if they are given a card, they must pose a question, and they can use the one on the card if they wish. This way, those few students are thinking of a question to ask while the presenter is working. The presenter also knows to expect questions, and the class understands that discussion of the solution is the norm, rather than passive silence. The other way I have seeded questions is to hand out a sheet to the entire classroom, and to tell them that you will call on a few students to pose a question, and that they can use the handout to help them formulate a question.
In either scenario, if I call on a student who claims to have no questions, then I will ask the student to paraphrase a specific part of the presentation, such as, "Could you explain what you think the presenter means by this line?" or "What is the goal of this part of the solution?"
The second way to get a whole class discussion going is to let a presenter complete his/her solution, and then to give the student observers 2 minutes to discuss the solution with a neighboring student in the room. Sometimes I will ask a pointed question to prompt the discussion, such as, "What kind of proof did the presenter use, and why do you think that was his/her choice?" and sometimes it is left open. Then, I open the whole class discussion by calling on students and asking, "What did you and your partner discuss?" This kind of question diffuses the pressure for students to report themselves as confused, because they often give replies like, "We were trying to figure out..." or "We weren't sure about..." The main idea is that students are more comfortable reporting on their actions in a partner discussion than identifying their personal confusion or misunderstanding.
The second way to get a whole class discussion going is to let a presenter complete his/her solution, and then to give the student observers 2 minutes to discuss the solution with a neighboring student in the room. Sometimes I will ask a pointed question to prompt the discussion, such as, "What kind of proof did the presenter use, and why do you think that was his/her choice?" and sometimes it is left open. Then, I open the whole class discussion by calling on students and asking, "What did you and your partner discuss?" This kind of question diffuses the pressure for students to report themselves as confused, because they often give replies like, "We were trying to figure out..." or "We weren't sure about..." The main idea is that students are more comfortable reporting on their actions in a partner discussion than identifying their personal confusion or misunderstanding.
