Great Ideas in education
I recently watched a Ted Talk given by Derek Muller, creator of one of my favorite YouTube channels, Veritasium. (If you've never heard of Veritasium, go check it out right now. You will not regret it!) In this presentation, Muller described his research on how to make a video that effectively teaches physics. He gave the students a pretest on a physics concept, showed them a video that explained the concept, and then retested the students after the video. What he found was that, contrary to conventional wisdom, videos that presented physics concepts in a clear, easily understood way did not improve student learning. In fact, watching videos that presented concepts in a clear, concise manner resulted students who were more confident but just as lacking in their understanding. As he put it, “A clear, expository summary is worse than no instruction at all.”
Muller found that when he instead presented each concept as a question and gradually revealed the answer through the process of a dialogue or in the context of an investigation, students said the videos were confusing… and their test scores doubled. When asked how much mental effort they exerted while watching the expository film and the dialogue film, students indicated that they exerted significantly more mental effort in watching the latter of the two films.
I interpret these results as evidence that cognitive dissonance is necessary for constructing knowledge. Students need to wrestle with a physics concept before they really understand it. The best examples of this are when a student is presented with a phenomenon that contradicts the student’s “gut feeling” or intuition: the lead weight falls just as quickly as the aluminum weight; the balloon inside the car leans forward, not backward when you accelerate; the spinning bicycle wheel stays upright even when hanging from a string attached to one side, etc. These kinds of puzzling cognitive experiences are what drive discovery in physics for doctorates and high school students alike. When faced with the bizarre reality of the natural world, human beings are forced to either justify it or look at it in a different way.
One challenge in presenting students with these kinds of dissonant cognitive experiences is that students can sometimes justify the phenomenon using a faulty conceptualization rather than reconstructing their knowledge. They reimagine the data to agree with their theory rather than reimagining their theory to agree with the data. One way to guide students along the path of sound scientific reasoning is to make use of what Harvard Physics Professor, Eric Mazur, calls “Peer Instruction.” Using this method, teachers give students the opportunity to explain their conceptualizations to one another and discuss their ideas, much in the same way that scientists discuss ideas with each other. More often than not, students end up at a sound, logical conclusion when they have the chance to bounce their ideas off of each other and engage in scientific discourse. Dialogue is crucial to constructing scientific knowledge.
Another challenge with teaching a physics class the way that Muller teaches through his YouTube channel is that cognitive dissonance takes time. It is a much slower approach to learning physics. That said, it is much more effective than simply throwing ideas at students from the front of the room and expecting the ideas to stick in students’ minds like cooked spaghetti to a wall. I think it might be worth it to have students learn physics at a slower pace in order for them to develop a deeper, more solid understanding. I want my kids to be enthralled with the beauty and wonder of the natural world – I want them to love physics for the inquisitive, existential journey that it is rather than memorize equations for a final exam. I don’t necessarily want to produce physicists; I want to produce people who can think like physicists.
I recently read one of Bill Ferriter's posts on how Interactive Whiteboards (also called "Smart Boards" in some circles -- here I will refer to them as "IW's" for short) are a waste of money. He made some interesting points about how IW's reinforce a teacher-centered model of education.
I had the opportunity to learn AND teach physics in a classroom that included an IW. In both experiences, I found that using an IW made sharing notes immensely easier -- students were able to easily access the notes online in the same format they had seen in class. That said, I'm not sure that having class notes posted online helps the students to learn better. For that matter, I'm not sure having the teacher give notes in the first place helps students to learn. It's certainly the way things have been done in the past -- it's the way I learned how to do physics, and here I am now with a bachelor's degree in my favorite subject -- but is it necessarily the best way to improve student comprehension? I'll have to revisit the topic of note taking at a later time...
In the meantime, I have to agree with Ferriter's argument that IW's take the traditional model of education and put it in a digital context. In other words, having the IW's doesn't really change the way we teach, it just changes the way we lecture and present. Excellent teaching, however, is a LOT more than just lecturing. In fact, the best teachers I've ever had were the ones that let us (the students) do most of the thinking. Based on my experiences with IW's, I must say that staying at the front of the room all the time makes it hard to give students opportunities to do most of the thinking. What else can a teacher do, though? I mean, with only so much time in the day and with so many things to "cover" in a class, surely we have to some amount of lecturing, right? Especially in physics, where students need to see how problems are solved before they can do it themselves, right?
I don't think we physics teachers have to lecture as much as we might expect. In fact, I think our kids could benefit a lot from using the old-fashioned whiteboards and giving us teachers a break from the front of the room. Take a look at some of the ideas that Kelly O'Shea has implemented, for example. She's got kids actively engaged in collaborative, evaluative, critical thinking activities where they are using mini-whiteboards as a way to visualize and share their thoughts. I've also used mini-whiteboards in my classes and found them to be an asset in formative assessments of my students' learning.
Interactive Whiteboards are a lot of fun to play with and can certainly do some amazing things, but I think the miniature, non-electronic versions do a lot more for my students' learning than the $2,000 variety.