I believe that the student who takes notes is more involved in the learning process. More senses are involved--not just sight and sound, but the cognitive process of summarizing the key points and the physical process of writing them down. The more active the student is in the learning process--that is, the more senses that get into the act, the more students learn and retain. True, some students are not as good at note taking as they should be, but the surrogate note-taker may be no better.

Students who take notes are more obliged to make sense of the lecture. They are forced to confront any source of confusion, and, as a result, may be more inclined to ask questions. Students who attend class without taking notes, however, don't have to explain to themselves through their notes the point being made by the instructor, so they may be less likely to confront their own confusion. More generally, they may feel less inclined to ask questions to clear up any confusion since they believe the store-bought notes will straighten things out later. Finally, to the extent that students believe that getting a set of notes is a prime reason for attending class, then buying the notes reduces the incentive to attend class.

I decided against the note-taking service. But I would be glad to hear from those who have had experience with this service one way or the other.

Raising key points in this way not only reinforces the main ideas presented but also provides a progress report both for me and for students. The rolling review checks the foundation to make sure the bricks added that day become firmly seated and don't just sink into the mud.

For example, one popular money and banking textbook uses color extensively. In the preface the author details 14 "pedagogical aids" of the book but says not a word about his use of color. What's more, the verbal explanations of figures and graphs make no reference to color. The books seems to have been written with no knowledge of what colors would be used or, indeed, whether multiple colors would be used. A more efficient use of color calls for a closer link between the verbal description and the color employed.

Another intermediate book, this one in macroeconomics, shades the background of each figure with colors that, in the same graph, range from bluish-green to pink. This shading makes the graphs look busy and adds no pedagogical value. I would describe this as the promiscuous use of color. This particular textbook's only explicit use of color in a consistent way is to shade boxes of words in the graphs. How ironic--the color is used not to identify systematically certain kinds of curves or certain areas of the graph, but to shade boxes that contain words, words that seem to clutter up the graph.

The reason color seems to be an afterthought in most textbooks is because it probably is. The division of labor typically sorts the task of book publishing roughly into the writing stage and the production stage. The selection of colors is often made in the production stage--akin to the choice of typeface, paper stock, and cover design. Authors should know at the writing stage what colors they have on their palette; they can then use color thoughtfully and effectively to enhance their story.

Color can be most effective in complicated figures. For example, in comparative static's, color can be used consistently to identify before and after equilibrium. Color shading can also readily identify and distinguish among areas such as tax incidence, profit, loss, consumer surplus, producer surplus, aggregate output below and above the economy's potential, and the welfare effects of tariffs and quotas.

Color even in relatively simple diagrams can aid students in ways we may not realize. This past term, a principles student explained to me that she had difficulty with the graphs presented on the blackboard. She said she has a certain kind of dyslexia that at times makes her see graphs in reverse. But she noted that graphs in the textbook were much easier to understand because they employ color consistently (e.g., demand curves are blue and supply curves are red). She says she first identifies the curves by color.

If color is to amount to more than face entertainment, it must be used consistently and with forethought.

For example, the classes in which students give the instructor higher ratings tend to be the classes where the students learn more. And an instructor's self-evaluation tends to be significantly correlated with student ratings. Student ratings are also correlated with ratings by faculty colleagues and by alumni. This last piece of evidence challenges the popular view that students appreciate quality teaching only after they graduate and are seasoned by the real world.

What biases are there in student ratings? Two issues that don't seem to matter are the gender and age of the instructor. But there is some bias. Regular faculty tend to receive higher rating than graduate teaching assistants. Students can be influenced more by style (e.g., enthusiasm) than by substance. Ratings tend to be better when the student has had a prior interest in the subject or is taking the course as an elective. Students tend to give higher ratings in courses where they have had to work harder. And students give somewhat higher ratings if they expect a higher grade, thought the bias here is not as strong as most think.

Ratings tend to be higher if students are required to sign their names, if the instructor is present during the evaluation, and if the announced purpose of the ratings is for personnel decisions rather than for self-improvement only. Finally, instructors who receive feedback from student ratings administered during the first half of the term do substantially better in ratings administered at the end of the term than do instructors without the benefit of the first rating.

Student ratings are far from perfect, but, if interpreted with care and used in conjunction with other information, they are probably more reliable and more useful than many of us think. The problem is that they are often relied upon as the primary, if not the sole, source of information about teaching. Nobody would claim that student ratings are the whole story.

• As a check on your effectiveness as a lecturer, ask a few students chosen at random after class if you can read their notes for that class. Do this a few times during the term just to see how well you are communicating.

• "Education is what survives when what was learned has been forgotten."
  
  B.F. Skinner

  I know of instructors who skip all the introductory chapters, including the chapter on supply and demand, and begin the course right in the middle of things. Then they wonder why students don't get it.

  We should be teaching students how to think, not what to think.

  Here is a test of rational expectations for Star Trek fans. Captain Jean-Luc Picard, Counselor Troi, and some new guy make up the away-team that has beamed down to the planet to examine a strange disturbance in the force field. One of them never makes it back to the ship. Which one? (Incidentally, isn't the Enterprise a great name for a future vessel of exploration?).

  Although our bias in the classroom tends toward the orderly transmission of information, a little more chaos might promote more learning. Why not encourage students to call out their questions and comments at any time, but especially when you do not notice a raised hand? For example, a student may need a clarification when you are writing on the blackboard (and your back is toward the class).

  Phil Saunders of Indiana University years ago argued that we should use mnemonic devices to help student grasp and retain new terms, such as perfectly Elastic curves and perfectly Inelastic curves.

  "It is the supreme art of a teacher to awaken joy in creative expression and knowledge."
  

  Albert Einstein

  "A moment's insight is sometimes worth a life's experience."
  

  Oliver Wendell Holmes

  "The most extraordinary thing about a really good teacher is that he or she transcends accepted educational methods. Such methods are designed to help average teachers approximate the performance of good teachers."
  

  Margaret Mead

  "Human history becomes more and more a race between education and catastrophe."
  

  H.G. Wells