Tuesday, December 6, 2011
A Modest Tactic for Improving Teaching
Yesterday’s lesson plan was fulmination; today’s is incremental improvement.
We—those of us who teach economics and other subjects—use exams and quizzes to evaluate students and assess our own effectiveness at reaching educational goals. Some questions are narrow and technical, others broad and open-ended. I want to talk about the narrow ones.
Narrow, close-ended questions are usually written to find out if the student can supply the correct answer. The information we draw from them is whether the student “gets it” or not. If not, and if there is enough time for it, we will go back and see if more explanation can facilitate the getting.
I propose the opposite approach: design these questions to see whether students have fallen into certain predictable errors. If they have, unteach them. The underlying conception behind this strategy is that the process of learning is not mainly, or at least only, that of gaining mastery over items of skill and knowledge, but also casting off false habits and beliefs. The mind is not a tabula rasa but a messy blackboard, and if you simply try to overwrite it you will often get more mess at the end. The critical tool is an eraser.
This is especially a problem in economics. Students are exposed to a vast amount of information about economic topics outside the classroom, and a lot of it is wrong. This exposure began long before they had the ability to question it, so false beliefs are often deeply embedded. Worse, there are powerful interests operating through politics and popular media who benefit from particular misconceptions and feed them incessantly. (Think, for instance, about why it is that most students entering their first macroeconomics class believe that inflation, by raising prices, reduces consumers’ real income—unaware that wages are also prices.)
If you want to organize assessment and teaching around error reduction, the key step is empirical. You have to spend a lot of time listening to your students, not to find out whether they are saying what you want them to say, but simply listening to what they are saying. What are their actual beliefs? How do they define for themselves the technical terms you are using in the classroom? How do they read equations, and how do they go about trying to manipulate them? Look for errors in clusters, common pathways that lead them away from the goal you are trying to reach. Then build the narrow questions in your exams and quizzes around what you have found, and use the results to guide your teaching in a more fruitful deconstructive direction.