The Problems with Physics First
Biology, then Chemistry, then Physics. In the United States that’s how it goes in most high schools, and how it has gone since the early 1900s. Some of you in certain school districts may have heard of a movement called Physics First, which proposes a reversal of the curriculum. I wanted to write a few words on that, giving both my support and my concerns.As a physicist, the idea of a Physics First curriculum strokes the ego. It also seems like a very logical way to consider things: starting with the most fundamental laws, building up into the more complex arena of chemistry, and ending with the exceedingly tough interactions of biology. (Fellow physicists, don’t fool yourself: biologists don’t use as much math as we do, not because they don’t have the gumption for it, but because their work is too complex for solvable equations.) The idea of building on previous, simpler concepts to create more complex structures is an appealing one to any scientist.
The problem is that we love our current courses too much.
For Physics First to work, to really teach students more effectively and more powerfully than the current bio-first curriculum, we simply can not teach our courses the way we do right now.
I’ll use the International Baccalaureate curriculum as an example – it’s world-renowned and well-respected, and unlike Advanced Placement courses, it is intended as a first exposure (AP courses are intended as a second course in the topic). Looking at the Standard Level courses, we find that IB Biology starts with statistical analysis and the idea of the cell, and ends with plant science. Chemistry begins with the idea of the mole, moves through a wide variety of topics, and ends with measurement and data processing. Physics starts off with measurement, motion, and force, and ends with energy, power, and climate change. All courses also have a variety of options that may be added, typically at the end.
Not only is this order of topics not conducive to a Physics First approach, it’s not even conducive to a Biology First approach. The topics do not dovetail, there is no harmonious joining of one subject to the next in the manner of a grand symphony of science. The IB science program is successful and well-respected by many measures, but it doesn’t sing.
We cannot simply change the order of existing classes and imagine that someone going into chemistry will actually benefit from a physics class that has nothing to do with it. If we’re going to have an intentional order to our science courses, we need to end physics with the atom, and start chemistry there. We need to end chemistry with organic molecules, and start biology there. We need physics courses loaded with chemistry concepts, and chemistry courses loaded with biology. Right now we teach these courses as individual, self-contained modules that could be strung together in any order. It doesn’t matter whether physics is first, last, or even optional. Who cares which one goes first if that’s how we’re going to do it?
And this brings up another important issue: students transfer. As a private school teacher I saw a lot of that. Our Junior class was huge compared to the number of Freshmen we had. There is indeed some benefit to teaching classes as self-contained modules when you consider someone coming into that third year of Biology from a different school. It could be overwhelming.
However, this speaks to a deeper need in our curricula. We lack innovation. If I’m going to teach a self-contained science class, it won’t be named “Physics,” much as I love physics. It might be named “ET and Exoplanets” and focus on the amazing things happening in astronomy and astrobiology right now. It might be “Energy,” going from the scientific definition of the word to modern-day power plants and solar cells. Were I a biologist, I might teach “Backyard Biology,” using the woods behind the school as a living laboratory and getting in-depth with the living organisms in our own neighborhood. I might teach “Epidemiology,” using a year to delve into viruses and microbial infections.
Who would ever want to take boring old Physics?
As long as we sit here pushing around the same three alphabet blocks and putting them in different orders, we’re not being innovative. We could be bringing in larger blocks and writing whole words on them. We could be building ramps and half-pipes, we could fit together stones of knowledge and create a tower of understanding. But no, we sit there and say, “Hmm, BAC or CAB?” And that’s why I think Physics First, on its own, is not a better way. We need to stop thinking small and start reaching for the stars.