How should the shape of your grade distribution change the way you teach?

I’ve received a number of comments about one of the recommended reads from last Friday. It was about the New York Times op-ed piece, about why people shouldn’t grade on a curve. And then, I asked, who does that anymore? The answer is: a lot of people. In addition to the comments on the post, I’ve gotten some emails and chatted with a few people (here while I’m at the International Congress of Entomology in Orlando, Florida).

One friend is in a department in which all faculty are rigorously required to conform their grades to a particular distribution, and they can’t submit their grades unless they follow this practice.

There was a second piece that reminded me of a topic that I’ve had in the queue of post topics for a few years. The link about how people often think they have bimodal grade distributions but they don’t actually have bimodal distributions. Quite a while ago — far enough that I can no longer recall or search it up — Jeremy Fox (of Dynamic Ecology) was thinking about if or how we should alter how we teach based on the structure of our usual grade distributions in a particular class.

I suspect many people think a central challenge in teaching is how to balance meeting the needs of high-performing students relative to the needs of the students who are challenging to just pass a class. Do you “teach high” and leave behind the struggling students, or “teach low” and fail to challenge the high-performing students?

In the last several years, I’ve come to decide that some of the teach-high-or-teach-low issues are predicated on a false premise. Students are in my class to learn a set of things that they don’t already know. This is both true for the struggling and high-performing students. The high-performing students can figure out out to get a high grade without much support from the course, because (for a bunch of complex reasons, independent of how smart they are, though I choose to defer to educational theorists about all that) they can figure out the things you need to get a high grade more readily. The struggling students, on the other hand, don’t have the academic savvy to garner high grades.

I want everybody in the class to learn the stuff that I want to teach. Oftentimes, the high performing students don’t necessarily learn the stuff, but instead, learn to jump through the hoops to earn the grades they want. So teaching high-performing students is not that easy, necessarily, because if they can take tests very well, then they can only just do what it takes to get their A and never really learn what you’re teaching. On the other hand, struggling students who haven’t figured out to do what it takes to get that A could be struggling mightily to learn the material, and may have actually learned more than the high-performing students, but the tests just don’t show it, because they’re not expressing what they’ve learned on the tests.

We learn by struggling. Like building muscle tissue from weightlifting, if you don’t struggle, can you grow? In my experience, it’s more difficult to get high-performing students to struggle on the material that you want them to struggle with. I don’t want to give high-performing students more “difficult” stuff to struggle with than other students, because I want everybody in class to struggle conceptual with the material that I am trying to teach. I don’t think that’s done by making it harder, but by ensuring the use of critical thought and analytical reasoning, even in topics that are not considered difficult to learn. I want to make sure that my high-performing students actually struggle. If As come easy to students, then that means I need to find a way to create a way for them to struggle without just giving them more stuff. I want them to find struggle in the things that we are covering so that they actually learn it, and not just be capable of getting an A. You want to create a way in which everybody finds a need to stretch their brains.

Let’s say there are two sections of an introductory course. In Class One, based on past performance, you’ll expect a bunch of students to get As, and the remainder to get Cs. In Class Two, based on past performance, you’ll expect the majority to get Bs, but with a range including As and Cs, and a tail to the left. In other words, in one class you have a clear bimodal distribution, in the other, a clear normal distribution.

In the bimodal class, in the K-12 model for sure, you’re expected to differentiate instruction, to provide support to each group of students in a different way. In a unimodal class, you don’t have two discrete groups in your class with differences in academic performance. At the university level, do you teach these two different sections differently?

That’s a sticky question for me. I don’t know how I’d deal with this hypothetical situation. What do you think?