Wednesday, February 04, 2009

Alternatives to Lecturing

Earlier this week, I wrote about two physics instructors who use vodcasting as a technique to replace traditional lectures with a more engaged classroom experience. I came across another article today (again on Reddit) from the 1960s, where a Professor Morrison lays out his case for what he calls The Gutenberg Approach. This piece is paired with a letter from 2008 about the discovery and use of this method, where Frank L. Lambert gives the following summary of the problem as he sees it:
The lecture system was crazy for teaching organic chemistry. What are professors doing in a lecture? They’re outlining and explaining the important points (and wasting time mentioning even obvious points) of the text on the blackboard. But why? Gutenberg invented movable type. That made printed textbooks available 500 years ago — even now in chemistry rather than alchemy! Students don’t read them? Of course not, if the whole course is dependent on what the prof puts on a blackboard! Students can’t pick out the most important ideas and facts from a 500-page text (in 1948, or thousand-page now) by themselves. They’re beginners.
This reminded me of something Bertrand Russell said in his biography, which my wife gave me for Christmas a couple of years ago. I can't find the exact quote, but he said that at university he never learned anything from the dons, and resolved that if he became one he would not expect his students to learn anything from him either. I think he was referring more to content than style, but both are clearly important.

The resignation to the students not reading the text is one I've experienced in my own career over the last couple of decades of teaching college math. A textbook literacy project, perhaps run by the school library, might be a way to approach this. Or a general reading campaign (here's an amusing take on that: faceabook).

The solution to the lecture/textbook problem is summarized by Dr. Lambert thus:
[W]hy not give them something a bit better than the [class] notes on the day or the week before the class, not really an outline of the text but more of a guide to what’s important and what’s not in each day’s text assignment. Then the students could read a day’s assignment and know what to look out for as the key points, realizing that the professor is not going to outline it on the board. Instead, she or he will explain in detail a few complex things in the assigned pages, answer any questions about them, and show how to conquer problems like those in the text, always open to questions and for back and forth with students.
This is an argument for a more engaged style like that of the vodcasting approach. The two are quite similar, in fact. The main difference is that a static outline has been replaced by video. The advantages of the second, to me, are that actually hearing words is better than reading them (for evolutionary reasons), and the animation possibilities inherent to the video medium are superior to plain text. Combined, the vodcasting approach has significant advantages for delivering information. For indexing material and outlining the important bits, I can see where a static outline would still be a great thing to have.

How might you try this out? This is a question I'm tossing around. There are the funding and nuts/bolts questions: how to actually record and distribute the material, train the professors, and so forth. Also is the need for a local champion to take on the project. Finally, one would like to assess the results of this, especially given all the time and expense involved. For the last part, Dr. Richard Hake [blog] has long advocated using pre/post tests for the sciences as a way to demonstrate accomplishment, and the research seems to support this position.

I spent some time Googling "alternatives to lecturing" and sifting through the results. Much of it is fairly obvious: use discussion, debate, Q&A, problem-solving, and so forth. More interesting is the idea to use simulations in class. This probably works best for technical fields, but has some advantages. In my experience, simulations can:
  • Teach deep connections with directed 'play'.
  • Teach software tools used in the profession
  • Teach secondary skills like programming
  • Link to coursework in an obviously applied setting
The first time I taught Computer Organization I wanted to combine an introductory digital logic course with the more advanced topics of designing the CPU, ALU and other bits of a working computer. There were simulators on the market, but they were complicated, expensive, and required high performance workstations. So I built a simplest-possible digital logic simulator in Perl, which I called Zlogic. I've used it over the years to good effect. In class, students learn how digital circuits work and how to write Boolean equations for different kinds of logic. With the simulator, they can enter those same equations and see what happens when they input data and run it. That is, there's a complete trial-and-error loop that can be quickly executed.

Perhaps the real problem with lectures is that they don't engage the learning part of our brain. How do we learn? By trying things and making mistakes until we get it right, I would say. Simulations and similar types of software can provide that.

In an other years-long project, David Kammler at SIU-C and I developed a software package for Fourier Analysis, which can be used to 'play' with the ideas. Here's an example I used in a grant application:

Load a vector, traced from an image. This is a complex list of values (meaning real and imaginary parts) plotted on the complex plane in the usual way.

Next we use a technique that would be learned in the course. We want to compress the information in the vector (the drawing) by looking at its frequency components and removing most of them.

The top part of the graph is the real part, and the bottom is the imaginary. The squiggly lines show the magnitudes of various frequency components. Most of the information is in the low frequencies, so I have zeroed out the higher frequency data to compress it. This is called a low-pass filter in engineering. Now we imagine sending the compressed vector of frequency data to our friend, who isn't fazed by the squiggles. She's had Fourier analysis, and knows that she should unscramble them by using the inverse Fourier Transform. Because we removed some of the information, the reconstruction won't be perfect. Here it is.
This all takes no more than 10 seconds to do, so the try/response cycle is very quick. The effect of the trial is obvious. One can easily go back and try different filter widths to see how much the quality of the final image improves. It's all very fast. In my mind I equate that with the speed of learning; the faster we make mistakes, the better.

An ideal program might be outlined like this:
  1. Facilitate the creation and use of vodcasts with a trial group of instructors, providing technology and support, probably through the library in combination with faculty development leadership
  2. Help the faculty member develop active classroom strategies to supplement the vodcasts
  3. Outline and index vodcasts, and put the technology in place to deliver them over the web
  4. Provide a textbook literacy program at the library and encourage use by the target group of students
  5. Mate the program to a software package that can do simulations quickly and easily
  6. Assess with pre/post tests on content
I've probably missed something obvious in this list, but this is a good start for thinking it through. I call this kind of thing making the preliminary mistakes. The quicker you get through those, the better.

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