“How much longer are you going to be?,” asked my husband from the door of our home office/guest room. It was nearly 11:00 PM. “I should be done in about 20 minutes, but you don’t need to wait up for me.” I was putting the finishing touches on my set of lecture notes for tomorrow’s class. Even though it was an introductory biology course I’d taught several times before, the topic was tricky to explain to first year students. We were going to cover the fundamentals of statistics tomorrow, in preparation for the week’s lab where the students were going to analyze the data set they’d gathered the previous week.
In preparation for tomorrow’s class, I had reviewed my notes from the previous time I’d taught this topic, as well as reviewed several note sets that colleagues had posted to our departmental website for the course. In addition, I had explored various statistics web sites, hoping to find some good examples to talk about in class. After assembling my electronic notes as slides to view on the classroom projector, I printed them out and wrote notes on them, thinking through how I would transition from slide to slide, how I would explain each concept, what examples I would use. Satisfied finally, just before midnight, I turned off the desk lamp and felt my way along the wall of the dark hallway, crept up the stairs, eased myself into my pajamas and slid under the covers. I hated to go to bed without unwinding with a glass of wine and a little television because my mind was still active and thinking about the class. It took quite awhile before I fell asleep.
Just before class the next morning, I looked over my notes and decided, at the last minute, that I would try to explain some of the basics using the chalkboard rather than whizzing through slides. My students were always telling me that I go too fast and I figured that the chalkboard would slow me down some. It’s difficult for me to use the chalkboard these days, particularly for highly quantitative material because if I write the incorrect number, I don’t always notice it and run the risk of confusing the class. In addition, for some strange reason, I tend to lose my train of thought when I turn back and forth between facing the board and the class. But, I reasoned I was well-prepared and had taught the concepts numerous times and the slower pace would really help the students.
As class began, I was confident and trying my usual best to sound enthusiastic about this fairly dry material on statistics. I tried a few opening joking comments about the thrill of statistics and the class, usually very responsive, seemed somehow leaden. I knew it was a difficult time of semester, with lots of assignments and subsequent all-nighters, but it still gave me pause. They just sat there, looking at me. “Uh-oh,” I thought, “this is going to be a tough class session.” I should’ve stuck to Plan A and used the slides. Unfortunately, I forged ahead with the last-minute Plan B, turned off the computer projector, lifted the screen and picked up a piece of chalk.
“Because these concepts are a little tricky,” I said to them, “I’ll slow myself down by using the board.” I began explaining the idea of a population and how to sample that population. You can describe various characteristics of that sample, the number of individuals (N) making up the sample, the range of measurements (highest, lowest), the average measure, etc. For example, let’s say you want to know about the overall weight of elephant seals. Realistically, you can’t really round up all the elephant seals in a population and weigh them. Instead, you might weigh ten elephant seals as a sample of the whole population, as representing that population. Your “N” is ten. You weigh all ten and have a range of weights. From this you can find the average, or mean, weight.
I went on to talk about variance, or how the weights of individuals in the sample differ from the mean. I turned to face the board, trying to come up with another example (I tend not to consult my handwritten notes when I’m using the board), when suddenly my mind froze. I simply lost the concept of variance. Even the word “variance” disappeared from my brain. I literally froze, chalk poised, facing the board. I thought, “This is an actual teaching nightmare, coming true.” The thought was so loud in my head that I was afraid that I’d actually said it out loud.
Often in the weeks before the semester begins, I will have teaching nightmare dreams, where I’m assigned to teach a subject I’ve never heard of. Or, where I walk into class, forgetting my notebook and having no idea what I’m supposed to be covering. Or, where I simply cannot find the classroom I have been assigned and I wander all around campus, entering elevators that are out of control, moving sideways or upside down. Anyway, I stood there for what seemed like an eternity, wondering if I should just put down the chalk and walk out of the room. What had I been talking about? I started vocalizing a stream of words. I knew they were incoherent, but I had to stall, hoping my train of thought would return. It didn’t.
I drew some vague lines and curves on the board while continuing to utter a stream of words, then put down the chalk and turned to face the class. There was a brief silence. A student raised her hand. “I didn’t understand anything you said. Would you go over it again?” I smiled, I hoped casually, and said “Sure thing.” I uttered more nonsense, pointed to the lines and curves on the board and glanced at the clock. Thankfully, I noticed that class would end in five minutes. SO, I stopped and said, “These are very confusing concepts. You all need to think it over a bit and we’ll revisit these in the next class.” After a surprised few seconds, because I never ended class early, the class slowly filed out, not even looking in my direction. I went back to my office, shut the door and burst into tears. I think I must’ve had a stroke during class or something.