How not to, um, be too bad

One of the main things that you might convince yourself of if you walked around classrooms at almost any high powered research institution – including my own institution – is that the ability to do something well and the ability to teach that thing well are totally unrelated. It’s not that there are not good teachers in these places – every place has some outstanding teachers – but you would never be able to predict who is going to be one of the good ones by looking at a CV or noting how famous the person is as an academic.

We all know this to be true.

So I was particularly amused the other day when I got an invitation to give a talk about how to be an effective teacher.

“I have no idea how to tell someone how to be an effective teacher,” I protested.

“But you’re such a good teacher you must know how,” I was told.

First rule of effective teaching: don’t assume that someone who is good at something knows how to teach it. Particularly if that thing is teaching.

I couldn’t really get out of it. Last year I won Caltech’s Richard Feynman Prize for Outstanding Teaching, which is a flattering shot of confidence that perhaps I am doing something right in my classroom, but along with the prize comes some responsibilities. Last fall I had to talk to a group of graduate students about how to be an effective teaching assistant (“Don’t overestimate how organized your professor is”) and I had to give a talk at a graduation lunch on a topic of my choosing (“Why it’s OK to feel like an impostor”). I have to speak at the big dinner before graduation this year (haven’t started thinking about that one).Talking about effective teaching was one of the things I had to do.

Three weeks before the talk I was asked for a title. I had not, of course, even begun to think about what I was going to say (Second rule of effective teaching: know what you intend to say). Jokingly, I suggested “Teaching: How not to suck,” knowing that they would not actually use such a rude title. So, of course, they did. And then they plastered signs with the title all around campus.

Such a shockingly rude title led to a higher-than-usual interest in hearing what I had to say. Plus there was free food. The lecture hall was relatively full. Sadly, though the talk itself kind of sucked (Third rule for effective teaching: don’t raise expectations unrealistically).

I did end up with a few things to say; I just didn’t say them in an organized coherent enough way to have it be useful to anybody who was in the audience. But being forced to think about how to describe effective teaching did give me time to come up with a few general principles, of which some have already been stated. Here are a few more:

Fourth rule for effective teaching: have a thin skin. Students always like professors who care, but they rarely understand exactly what that caring really means. Yes, it is important to me that I teach effectively and students learn what I think they are supposed to be learning and they’re not bored. But I also have a very thin skin. To be short (and rude): I hate to suck. I really really hate to suck. And, believe me, sometimes I do. Students out in the audience of large lecture halls think they are very clever about surreptitiously falling asleep without being noticed. I always notice. There are days when I lecture and I simply know it is not going well. I am not clear; I ramble; I say things in the wrong order. And when I leave the lecture hall I feel simply awful. And I go back to my office and think “I do not want this to ever happen again” and I work hard on the next lecture. But not really because I am a magnanimously caring, but because my skin is too thin to have this happen too many times.

Fifth rule of effective teaching: lecturing is bad. I am fairly convinced that lecturing is one of the least effective ways of transmitting information ever invented. We lecture because that is what the monks did in the medieval times before they had books or computers or videos, and no one seems to have really thought very hard about whether or not this makes any sense anymore. So why do it? I challenged my audience during my talk to come up with any reasons they could think of for why lecturing might be useful. They had three thoughts: (1) It might be entertaining; (2) It might aid memory; and (3) It might aid comprehension.

Is any of this true? Who knows! But simply asking them the question totally changed the dynamic of the lecture. They were no longer passive recipients of wisdom from me, but active participants in trying to figure out what was going on. The change in the room was obvious. People sat up in their chairs; eyes were opened; hands were raised. And all of this means, I think, that brains were engaged. They will remember this part of the lecture more than any other part, and when they stand up in their own classes to give lectures perhaps they will think to themselves “why am I lecturing” and they will at least be thoughtful about what they are doing.

The point, of course, was to demonstrate that lecturing is bad. Engaging is good. I do think that a classroom section can be entertaining and aid memory and aid comprehension, but I think that this rarely happens when I stand and deliver a one-way lecture. If it’s one way it might as well be a video, which is significantly more efficient.

Sixth rule of effective teaching: humbly remember your days of ignorance. I teach a class on geology. Conveniently, I know very little geology. I thus relate quite strongly to my students who are seeing these concepts for the first time. I actually think that it would be very clever to require that introductory classes are taught by relative outsiders to the field.

Seventh rule of effective teaching: never ever go late. All students will hate you even if you are the most informative and entertaining person in the world. Fifty minutes after the start, not a single person still wants to be around. The same is true here, thus I end.

Nervous gyrations

On Sunday May 11^th, at 6:53 PM, looking from my backyard, the sun will still be appealingly gleaming above the western horizon, with almost an hour to go before it sets. Almost straight overhead the almost-first quarter moon will be waiting to steal the show as soon as the sun is gone. But I won’t be looking at either one. My eyes will be focused just above the eastern horizon where my current favorite outer solar system object – 2003 EL61, better known as Santa – will just be rising. OK, so I won’t see anything but blue sky; even at night Santa is about 10,000 times too faint to see with the naked eye. But I’ll be looking that direction thinking about the fact that at that moment the Hubble Space Telescope will be joining our hunt for moon shadows. On May 11^th and then four other days over the following two week period, the telescope will come around the earth, swing towards Santa, and snap a quartet of pictures to help us determine precisely where the small satellite (aka Blitzen) is.

This is good news! Without the Hubble we feared that it would be another year or two before we figured out the orbit well, and in that time it was quite possible that shadows of Blitzen would no longer be falling on Santa. The case that we made in our emergency plea to use the telescope must have been compelling; within two days of sending in the proposal we had heard back that we had been approved. But there was some bad news, too. Hubble is approaching two decades in space, so things sometimes fail. Visits by the space shuttle continually fix the Hubble back up and add new capabilities, but with the space shuttle fleet itself barely limping along, Hubble has gone without a visit now for more than six years (a new visit is scheduled for late summer). In that time some of its gyroscopes have failed.

Gyroscopes are critical on a spacecraft like the Hubble, because they keep track of which direction is which. They work just like a spinning top works. As long as the top stays spinning fast it stays pointed in the same direction (in the case of a top that would be up); as the spinning slows the top starts to wobble and finally falls down. In space, with no gravity, the top would just keep spinning in whichever direction it was originally pointed. If the spacecraft does some maneuver to point in a different direction, the top still stays fixed pointing in whatever direction it started. Tops – which is all that gyroscopes really are – are great for space, because, with no gravity and no compass, there are not many other ways to figure out which direction you’re pointing.

If the Hubble had no gyroscopes left it couldn’t do anything. Luckily, three still survive. With three gyroscopes you can point anywhere in space at anytime. Wisely, though, the people who run Hubble decided that it was better to keep one in reserve in case one of these last three fails. So Hubble operates with two gyros. With only two you can still point to anywhere in the sky, but not at anytime. And this where the bad news comes in. After about noon on May 24^th Hubble can’t observe Santa again for a few months.

The people at Hubble wanted to know: was it still worth doing the observations? We had to ponder. We think Blitzen takes about 19 days to go around Santa. From May 11^th (which was the soonest we could get on the telescope) until May 24^th is only 13 days. So we won’t see the complete orbit, but we think we’ll see enough to be able to calculate where Blitzen is the rest of the time. “Proceed!” we said.

But then there was worse news. Hubble uses the gyros for course pointing, but for keeping the telescope absolutely still during the course of the observations it also tracks a pair of bright stars close to the target. And, by bad luck, there aren’t enough of them close to Santa. A single star is available up until the 19^th, and then absolutely nothing. We can do the observations, slightly degraded, with a single guide star, but there is nothing to be done after the 19^th. So now we were crammed into May 11^th through the 19^th, an eight day window, when we really had hoped for a full nineteen day window. They asked again: is it still worth it?

By luck, if you only had eight days out of nineteen, these might be precisely the eight days you would want. They are when Blitzen is closest to Santa, which is the part of the orbit we need to know best. But still, it’s going to make our lives even harder than before. Will it still work? We did some quick calculations and decided, once again, we could do it. So we’re on for our eight days in May.

Now I’m nervous. We promised a pretty spectacular result to the people at Hubble. We need to deliver. There is always the chance that the new data will show that the shadows just finished happening and we’re too late. That would be bad luck, but we could at least hold our heads high and say we figured it out, just a little late. No, what makes me nervous is the possibility that we will get the data and still not be able to figure it out. People will say: OK, what’s the answer? And we will have to say. Well, um, we still can’t quite calculate the orbit. We can’t tell you when there will be moon shadows. Wait until next year.

I don’t think this will happen, so mostly it’s just paranoia. And I always have it. Every single evening when I am sitting at big telescope and the sun goes down and the dome shutters open I get similarly nervous. What if we did something wrong and all of our careful calculations about what we are going to look at and what we might discover were wrong? What if we forgot to take something into account? What if there is a better way to be using the telescope? What if…

And then the sky darkens and our first targets appear on the screen and I forget all of the nervousness and worry and get to work.

The same thing will happen, I hope, with this project. I won’t be at the telescope this time. I’ll be sitting at my desk sometime a few days after May 11^th, when the data finally get transmitted and processed and downloaded onto my computer, and I’ll pull up the first image and forget all of the nervousness and worry and get to work.