Mar 23, 2012

Khan Academy II: Discussions and "Khanversations"

"Khan Academy" style instructional YouTube videos could be more effective for introductory physics if they used a discussion model rather than a lecture model.

I had a fine time last week at the WNET Channel 13 Celebration of Teaching and Learning (which consisted of about 30% substance, 20% patting teaching on the back for doing "such an amazing job," and 50% advertising), and I wanted to follow up on the post I wrote about Khan Academy.

Over the course of the day, I saw Sal Khan (the Silicon Valley superstar shown in the camera-phone screens to the left) give his standard talk, and then follow it up with an hour-long question and answer session. In general, I came away convinced that Khan's heart is in the right place, and that Khan Academy strives to be far more than a YouTube channel. The goal of Khan Academy, he said numerous times, is to off-load a number of tasks traditionally done by teachers in order to free up the teacher's time to do more valuable things. During the Q&A, I got a chance to ask Khan essentially the questions that I posed in the last post: What is the role of an explanatory video when we know that clear and concise explanations can be counterproductive to student learning? His answer was basically that students should have access to whatever resources that might be helpful to them, and they're taking seriously their responsibility to measure the effectiveness of the videos to identify which ones aren't working. Here's a quote from his response:

When I think about my own learning, there are some times when I learned something through the experiential, where finally when I had to write a program when I was doing some computer graphics, trigonometry finally kicked in... But for some things, you know, especially when I was doing higher level math, it really sometimes was a friend in a coffee shop giving me a clear and concise explanation. And I was just like, "Wow, that really hit the spot. That was really much better than what was in the book, and that got me through my stumbling block."

I agree with what Khan is saying here, but this response reveals a slightly simplistic view of how learning works. I can't deny that clear and concise explanations from friends or teachers have gotten me through some tricky spots as well. However, I'd also suggest that hearing those explanations in clear and concise terms sometimes didn't actually help me as much as other approaches might have. Precisely because I was hand-fed exactly what I needed to fill in the gaps in my understanding at that moment, a few days or weeks later, those gaps sometimes returned.

When I think about what Khan Academy videos might look like if they were truly out to correct student misconceptions about, say Newton's Third Law, I imagine something more like the "dispute between students" prompts you find in Lillian McDermott's Physics By Inquiry books (see my previous post on this topic). In the Khan Academy model, picture a "Khanversation" between two voices, in which both individuals make arguments supported by diagrams to support a claim their view is consistent with observations in the natural world. This approach would provide opportunities to bring common misconceptions out into the open and model effective argumentation for students as they practice these concepts and skills in their classroom.

In a 2010 review paper in Science, Stanford School of Ed Professor Jonathan Osborne calls attention to a great irony in many science classes - traditional science teaching fails to develop the skills of argumentation and debate that are at the heart of the way science actually operates. Not only do student-centered teaching methods help to develop these essential skills, they also facilitate learning of science concepts far more effectively. Osborne writes: "Learning is often the product of the difference between the intuitive or old models we hold and new ideas we encounter. Through a cognitive process of comparison and contrast, supported by dialogue, the individual then develops new understanding. Consequently, learning requires opportunities for students to advance claims, to justify the ideas they hold, and to be challenged." We should be teaching our students first and foremost how to navigate their way through this process, as this is a skill that will be far more relevant to them than any science concept. (excepting, of course, Newton's Third Law...)

One of the most productive aspects of whiteboarding is that students are expected to formulate a verbal argument to support their answer, and present this argument to the teacher and their peers. Not only does this give a teacher instant access to their students' reasoning, but the students themselves are constantly exposed to effective and ineffective arguments. What role might other methods play in this process? I have tried to use handouts to structure and spur dialogue between students, but I've never gone so far as to upload such a dialogue to YouTube. At first glance, however, this possibility seems intriguing.

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