I haven’t blogged recently, but in the midst of a pandemic, when teaching is really hard I take the art and the craft of teaching more seriously than ever. Unfortunately the phrase “those who can’t do, teach” has become a popular motto, bolstered by the way in which teachers are generally treated as simple public servants rather than highly educated and trained professionals. Along with this comes all of the opinions that everyone has about education. The common rebuttal is that just because I’ve been sick doesn’t mean I diagnose and treat myself…I go see the doctor.
It seems that everyone thinks they can teach, but teaching is hard. Teaching physics is harder. Teaching so students can be successful on AP Physics 1 is arguably the hardest endeavor I’ve taken on.
So The Physics Girl, Dianna Cowern, has decided that she is going to teach the world physics. Specifically for the AP Physics 1 exam. I have loved all of Diana’s work since I caught her “what is color” challenge video and I have used many of her videos ever since to excite and inspire students. Dianna has a degree in physics, worked and studied at top institutions, she has also done extensive outreach work prior to being a major scicomm personality and has received numerous accolades for her work in education. I love and have great respect for Dianna and her work. Naturally, I wanted to watch her Physics 101 videos to see if they would be a great resource for my students. I’m always looking for good resources, especially right now.
Sadly, I was completely disappointed, although not particularly surprised. I shared a quick blurb on Twitter and quickly got attacked by random followers of hers. One even asking “as a baseline, what is your physics education”
Over the years I’ve learned a great way to get a sense of a source’s pedagogy in physics is to check out how they discuss work and energy. You could argue that the whole of science is summed up in this topic.
In my course, and in AP Physics 1, we start by defining systems. Then we can discuss how work adds or removes energy from the environment to the system and the transfer of energy within the system. We spend several days working with these conceptual models before even touching equations or calculations. Dianna’s video starts by defining work as force times distance. I will be the first to admit that this is exactly how I started the unit when I was a novice teacher! That is part of the trouble, as a novice you tend to teach how you’ve been taught, not necessarily through evidence based research methods (an unfortunate pitfall of too many teacher prep programs). From there, you have to get about half-way through the video before Dianna begins to explain the concept of changes, transfers and reference points. This part of energy is absolutely critical to comprehension, but it is a side conversation without any accompanying visuals or further discussion. Instead, she jumps into the potential energy calculation.
Another topic that I’ve shifted over the course of my career is forces. Within the #iteachphysics twitterverse we had intense conversations about inertia (thanks Joe) and why the typical phrasing of Newton’s Laws is problematic. When I taught Newton’s three laws formally, I had my students change the words “action” and “reaction” in the third law to “force”. Furthermore, I now define a force, not as a “push or pull” but as an interaction between objects. This is so important because it now becomes really difficult for students to make up random forces. Students love to make up random forces on force diagrams. Fapp shows up all the time, but when you require students to define a force as an interaction and name the objects interacting, not only does the ambiguous Fapp become obsolete, Newton’s third law becomes a natural consequence.
However, aside from these language and pedagogy criticisms, my problem with Dianna’s work runs far deeper. Physics has the reputation of being too hard for most people to do or understand. Dianna has this incredible platform that has made physics accessible and interesting to so many people. On top of it, she’s not an old white guy with spectacles talking about the secrets of the universe, she’s a bubbly, attractive young woman and she frequently features a diverse range of other scientists in her videos. This is such important work and cannot be diminished. She had an incredible idea to create these videos and they really could have served as an incredible launch point for students interested in physics thinking “maybe I can do this”
Unfortunately, in our nation only 24% of teachers who teach a physics course have a degree in physics. I don’t have the numbers, but I would argue even fewer pay attention to the latest in Physics Education Research and evidence based methods. The biggest challenge in teaching physics is helping students work through the first 6-8 weeks of the course. I am very clear with my students that this is a normal adjustment period that all first-year students of physics experience regardless of age or level of the course. The challenge in physics is that to truly tackle problems efficiently you need to be able to look at a problem, identify the big idea, and then pull out the necessary components about that big idea to apply to the problem. This is what has been defined in the research as “expert thinking” which differs from “novice thinking”. Essentially, a novice will see a problem and try to force it into a previous homework problem based on whatever minutia is presented to them. A great example of this is when my AP students are presented with a graph of velocity vs time of two objects and they are asked to determine if there is an external force. To be completely honest, most students just guess. They typically say “no” because the velocities end up coming to the same place on the graph. The expert recognizes this as an Impulse-Momentum problem. The expert will then find the change in velocity of each object and see if there is an equal transfer of momentum between the two. Asking students to approach problems in this manner has never been required of them before, especially at the high-school level. The only way to get students there is to model the process, and require them to actively engage and wrestle with the material frequently. None of this is about equations. Equations and math are simply the tool. Weaving the concepts together and identifying what is important is the art of physics.
When I made my initial post I had a lot of backlash from random, non-educator followers of Dianna insisting that physics is math therefore I shouldn’t criticize the math approach in the videos. What Dianna’s videos are creating is a misleading sense of familiarity with equations, but familiarity is not comprehension, nor is it what is required of a physics student. Physics students need to be able to apply and synthesize concepts in order to properly apply the mathematics. I often tell my students that math will never be the hard part of this course. Half of my AP1 students are taking calculus, and the hardest math thing in AP1 is solving a system of two equations! As for familiarity with equations, if that was all that was required to be a great physics student then the equation sheet should serve as a cheat-sheet to success. Teaching physics is truly an art, and I am 100% confident had Dianna reached out to excellent AP teachers she would have had lots of wonderful ideas and support. Once again, teachers are put on the sidelines and our expertise is neglected.