In this section, Dennis Freeman shares how the practice-theory-practice approach has helped him become more aware of students’ understanding during lectures. He also discusses how this approach has helped him interact with students at their level during labs.
Learning to Attend to What Students Hear, Instead of What Instructors Say
As a student, I learned in broadcast mode, and this was also the way I taught for many years. In broadcast mode, the lecturer stands at the front of the room, delivers content, and this is supposed to result in students understanding the content. In other words, if you speak it (in lecture), they know it (in practice). But it just doesn’t work that way.
I know, because I interact with students in the lab immediately following lecture. I have often given what I believed was a dazzling lecture, only to find that students in the lab hadn't understood even a small fraction of what I had talked about. In one instance, for example, students weren't able to apply the content of the lecture to the circuits that they were designing, even though, for me, the lecture had explained everything.
The practice-theory-practice approach is learning-centric, rather than teaching-centric, and, as a result, I’m now much more cognizant of what students are actually understanding. I’ve come to realize that it’s not so important what I say; it's more important what students hear.
Using Concept Questions to Assess Students’ Understanding During Lectures
Since implementing the practice-theory-practice approach, I’ve become more careful to assess students’ understanding during lectures. I do this by asking a concept question 
every 15 minutes or so, much like Eric Mazur does at Harvard. Students work in pairs to answer the questions. I show them five possible answers, and they raise their hands showing some number of fingers that corresponds with their answer choice. I look at their responses. If everybody gets the question right, I know I don’t need to explain the concept again. I keep going. If some students get the question wrong, I provide more explanation. If everyone gets the question wrong, then I know I didn’t explain the concept well and I start from the beginning.
[I]t’s not so important what I say; it's more important what students hear.
—Dennis Freeman
If the questions are too trivial, the students get bored. If the questions are too hard, students see the situation as hopeless and are less motivated to respond. To properly probe their understanding, you really want to ask questions that almost reach their zone of proximal development (Vygotsky, 1978), that intellectual space in which students can tackle the questions with guidance from the teacher. It's not easy to write questions that hit this sweet spot. The first year, our questions weren't very good. Over the years, we've learned to write better questions, but not every question that I ask every year works.
It's been very rewarding to get real-time feedback on the lectures. Students are engaging with the lecturer in a way that is different from watching a video. It's not a conversation, or point-to-point communication, as they'd say in communication theory, but it's less broadcast-based. It's somewhere in the middle.
Interacting with Students at their Level During Labs
It’s my belief that even the most brilliant lecturers are either talking to the bottom part of the class and boring the top, or they're talking to the top part of the class and just burying the bottom. It's just impossible to address, in broadcast mode, such a big range. The nice thing about our practice-theory-practice course is that most of the teaching is done in the lab. When I'm talking to a student in lab, I adjust what I'm saying to match the student’s current level of understanding. If the student has never seen programming before, I don't use advanced programming comments in the way I talk to them. If they've never seen a circuit before, I don't use jargon. I've learned how to say things without using jargon.
On the other hand, if I can see that I'm talking with somebody who's better at programming than I am, I say, “Well, have you done a list comprehension?” It comes right back to our practice-theory-practice approach and Vygotsky’s zone of proximal development. You want to interact with students at the right level. It’s hard to do that in broadcast mode.
Reference
Vygotsky, Lev. Mind in Society. Harvard University Press, 1978. ISBN: 97806745762292.