The Seven Deadly Sins of Teaching

Saturday, August 4, 2018

I was having a discussion with a friend of mine over dinner at JSM 2018 in Vancouver. We’re both passionate teachers. A couple things came up in conversation that I deemed two of the “seven deadly sins of teaching.” To avoid giving the mistaken impression that I might be sitting on a stockpile of knowledge regarding some five additional deadly sins, I clarified (as I devoured my greasy, well-seasoned, and well-ketchup’d fries) that I didn’t actually know what the others were. We agreed that compiling this list might serve as a potentially interesting homework assignment for me. I’m happy to report that this has been the work of my returning flight to the east coast! Brian, this is for you!

My views are undoubtedly shaped in large part by my own personal experiences (both as a teacher and as a student). I strongly suspect that this post is rather slanted in a way that is most applicable to the teaching of highly motivated and outstanding students. I also suspect it’s even more rambly than what is typical for me, given that my editing time was cut off by some turbulence. Nevertheless, I tried to keep my list general, high-level, and applicable to most (if not all) fields. To be truthful, I have fallen prey to each of these so-called “seven deadly sins” at some point in my 11 years of being an educator, so take these ramblings as more of a “what I think I’ve learned” than a “what you should learn from me.”

Also, don’t expect many comments on particulars of teaching methodology, in the sense of presentation style, forms of assessment, and so forth. There is too much variation across the disciplines and between instructors to fairly comment on such matters in a way that wouldn’t just merely turn this into “The Post of Andrew’s Arbitrary Opinions on Teaching.” Though it may be just that, regardless. I’ll do my best!

That said, let’s begin! What made my list of the seven deadly sins of teaching?


1. The “less is more” paradox: remove the bells and whistles.

Ostensibly, we really like what we do. We want other people to like what we do, too! We know a lot about our respective fields (even if the many of us suffering from imposter syndrome feel as though we don’t). We want to pass our knowledge on to enthusiastic students, which sometimes seems as though it might mean exposing them to as many topics in a term as we can justify.

To be sure, it’s quite easy to underestimate how long it’s going to take to teach a particular topic. If we’re adding tangential, non-essential material, this compounds the issue. The risk in this is the implication of less available time for core content. What’s more, if one is forced to substantially slow down the pace of the course, and as a consequence cannot get to all the topics “promised” in the syllabus, he or she risks leaving enthusiastic students with a feeling of disappointment.

I commonly have to remind myself that it took me years to understand the material I’m teaching at the depth I currently do. It really is totally okay not to cover every topic that could conceivably fall under the umbrella of the course description, and it’s also okay if a student finishes the course without the deepest appreciation for how all of the course topics interconnect. That can (and often does) come later, in large part on the student’s own terms and in his or her own way.

So you have a topic in mind, and you’re trying to decide “in, or out?” A good rule of thumb, in my opinion, is to ask yourself the following question: “would a motivated student, upon mastering the rest of the required topics, be able to use what he or she learned in the class to successfully acquire knowledge of this topic independently if he or she desired to do so?” If the answer is “yes,” then you can probably leave it out. The irony is that, if you do leave such a topic out, you have more time to cover the essential material, thereby making it more likely that the student will understand the said material better, in turn improving the chances that indeed the student can successfully learn the “additional topic” independently later. In other words, less is more. Go ahead and take out the bells and whistles and I suspect you’ll be pleasantly surprised with the result.

My strategy is to draft a fairly detailed course schedule to the best of my ability several weeks in advance of teaching the class. Once I’ve done this, cutting the extra things is almost always a great idea, but I try always to be very skeptical about adding in more (I use the same strategy for drafting exams and homework assignments). Another option is to include the extra material as optional material for homework assignments (but see #5 below).

2. The problem of the rut: keep it fresh!

We don’t want to be bored when teaching. Creating slide decks, exams, assignments, etc., takes a lot of time, and it can be tempting to recycle these things from year to year. This is a completely valid temptation, particularly for those of us who are also very passionate about our research and for whom teaching is not a primary source of salary. There are some dangers associated with getting into a rut and not changing things up from year to year. Not the least of which is that the novelty can wear off and we may subsequently lose the ability to comprehend what it’s like for a student not to understand the material, putting us out of touch with the class and its needs.

The good news is that if one is experiencing what he or she perceives to be a bit of a rut, there are a lot of things he or she can do just to spice things up from year to year that don’t involve a complete overhaul of the course materials.

  • Try to rotate off a course after teaching it x number of times in a row (x depends upon you, the class, the department, your obligations, your opinion). You can always come back to it after you’ve had a few terms off, and you may be surprised to come back seeing the material differently after a break, ready and motivated to use new examples from your experiences since you last taught.
  • Ask your enthusiastic TAs if they might like to write any homework or exam problems. Of course, use your judgment to make sure this doesn’t encroach upon their other obligations, but writing problems can be a good experience for them and takes a small amount of the burden off of you.
  • Think about whether the order of some topics could be shuffled. We sometimes teach things in a certain order just because of some arbitrary precedent. Granted, in a college calculus course, there are only so many liberties you can take. The biggest variation I’ve seen is whether or not the transcendental functions receive their own chapter or get interspersed throughout the other main chapters on differential and integral calculus. I’ve done it both ways, and didn’t really get the sense that there was a right or wrong. But because I did it both ways, I learned something about the advantages and disadvantages of each, and I was forced to come up with some new examples along the way to keep myself motivated and excited about the content.
  • Share materials with your colleagues (at your own institution or even at others) and ask them if they’re comfortable sharing with you. Just borrowing a few examples from their notes or assessments can alter and modernize the way you present it to the class, but more importantly, it may enhance your enthusiasm for it, which is equally important.

Not to get too controversial too quickly, but here’s the other harsh reality: technology has changed not just the way we teach, but the way we learn. In the modern era, you should assume any (if not every) student has access to the course material from the past several years. Whether you consider it cheating for them to use any of those materials is your call, and, as I respect this is a controversial matter, I am not here to make judgments on which side of the argument you’re on. However, if you don’t wish for students to be able to successfully complete a course by relying nearly entirely on a previous year’s keys, it may help to consider some of the options above.

3. The regret of not allowing silence: the awkward pause is your friend!

This one is pretty self-explanatory. The silence that is eating you alive is not actually as long as you think it is. It’s only long to you because you know the answer you’re looking for. Giving students a bit of time to work on the problem independently is a good thing! Not giving the answer right away is a good thing! Keeping the students engaged and active is a good thing! Each time you plow through the material, you’ve missed an opportunity to see what they really have grasped.

Relatedly, one of my challenges as a teacher is recognizing the difference between boredom and confusion. Hey, maybe it’s both, right? Giving a few moments to let people think about questions they have is a smart idea. If you struggle with the silence, maybe count to twenty (Mississippilessly or otherwise). It’s been remarkable to me how often I assumed there were no questions only to wait and find out that at least three people just needed time to formulate and execute a well-crafted question or insight that–usually–ends up contributing immensely to the course discussion.

4. The curse of the second-time teacher.

I’ve heard from many fellow educators a quote that goes something like “when you’re teaching a class for the first time, it’s like you’re a new teacher all over again,” This definitely has rung true for me over the years. I’ve been known to say, in return, “the only thing harder than teaching a class for the first time is teaching it the second time.” It’s a little bit of an exaggeration in the sense that you don’t have to do an entire new course prep, so that’s grand. But there are a couple of potential pitfalls to be aware of.

So you did something the first time you taught that truly worked. They really aced the material after you explained it using that one phenomenal example. Great! Now it is so easy to believe that you’ll get the same desirable outcome on the second try. You may! But be prepared not to get the same magic the second time.

Make no mistake, it is just as easy to overreact to things that didn’t go so well the first time. Perhaps you need to overhaul the ordering of the topics, totally scrap the notes and start from scratch? Possibly–but it’s just as conceivable that a small tweak will do the trick just as well! Until you try it, you really don’t know. And therein lies the struggle of the second year.

What it boils down to is that it’s not always easy to know why something worked or why it didn’t. I have to occasionally remind myself that the most important thing is whether or not it’s working in this class, and not whether it worked previously. Often, it’s a better strategy to try small changes before resorting to a complete overhaul.

5. The sin of extra credit on a curve.

Okay, if ever there is going to be something in this post that’s going to push some buttons, it’s probably this! To be crystal clear, there is nothing inherently awful about grading on a curve (for the right reasons), and there is nothing wrong about providing extra credit opportunities. I’m not here to criticize either of these things on their own. I also want to be clear that when I say “grading on a curve,” I don’t mean scaling the grades–I mean when you literally assign numerical percentages or letter grades based largely on percentile rank.

I would posit, that by both grading on a curve and providing extra credit opportunities simultaneously, you’re punishing students who perform at a satisfactory level, but may choose not to do the extra credit (for whatever reason, owing to ability or time constraints). Take Students 1 and 2, each having a perfectly respectable B average. Student 2 chooses to complete the extra credit and moves up in his percentile rank. Oops, now Student 1 has moved down in his percentile rank, perhaps even enough to bump him or her down to a B- average. Was that really your intention when you assigned the extra credit?

This issue has a surprisingly simple fix. First, curve the scores to your liking without any extra credit counted toward the average. Then, add the extra credit on after, without altering the grades for anyone who has not done the extra credit. By doing this, those students have not been unfairly punished for not doing the extra work.

Just as a note, I tend to prefer sensibly scaling grades where appropriate rather than relying completely on a curve. This may be a better philosophy for the kinds of courses I teach and may not apply overall.

6. The pride of the teacher.

This one is simple. It’s easy to take criticism of your teaching and your course as criticism of you. It’s human nature to be defensive, but plainly put, it can really help your teaching immensely to try to overcome that and take criticism to heart. Likewise, it can hurt your teaching if you resist any and all changes.

One thing you may consider is asking a peer or colleague you trust to come in and observe you and provide feedback. By having some control over the situation in which you will be evaluated, it may help you be more receptive to the criticism.

7. The need to be liked.

There’s a simple reason this one is last–because it’s probably the one everybody expected to be on the list. It’s also simple. We want to be liked personally. It’s more important to have a solid command of the material, present it well, and have the respect of your students than it is for them to personally like you. Look, let’s be real. I have a quirky sense of humor at times and it definitely comes out when I present. Some people are going to like it, and some people might not. That needs to be okay! It’s good to just be you and enjoy the experience.


So there you have it! Now, under no circumstances does it mean you are a bad teacher if you’ve fallen into any of these traps. It’s great to have opportunities to reflect and to engage in dialogue about best practices. That said, got some “deadly sins of teaching” of your own? Feel free to add your comment below. Until next time!