"Could you repeat the question?"

In recent years, that has become the most common response to questions I pose to my law students at Georgetown University. It is usually asked while the student glances up from the laptop screen that otherwise occupies his or her field of vision. After I repeat the question, the student's gaze as often as not returns to the computer screen, as if the answer might magically appear there. Who knows, with instant messaging, maybe it will.

Some years back, our law school, like many around the country, wired its classrooms with Internet hookups. It's the way of the future, I was told. Now we are a wireless campus, and incoming students are required to have laptops. So my first-year students were a bit surprised when I announced at the first class this year that laptops were banned from my classroom.

I did this for two reasons, I explained. Note-taking on a laptop encourages verbatim transcription. The note-taker tends to go into stenographic mode and no longer processes information in a way that is conducive to the give and take of classroom discussion. Because taking notes the old-fashioned way, by hand, is so much slower, one actually has to listen, think and prioritize the most important themes.

In addition, laptops create temptation to surf the Web, check e-mail, shop for shoes or instant-message friends. That's not only distracting to the student who is checking Red Sox statistics but for all those who see him, and many others, doing something besides being involved in class. Together, the stenographic mode and Web surfing make for a much less engaged classroom, and that affects all students (not to mention me).

I agreed to permit two volunteers to use laptops to take notes that would be made available to all students. And that first day I allowed everyone to use the laptops they had with them. I posed a question, and a student volunteered an answer. I answered her with a follow-up question. As if on cue, as soon as I started to respond, the student went back to typing -- and then asked, "Could you repeat the question?"

When I have raised with my colleagues the idea of cutting off laptop access, some accuse me of being paternalistic, authoritarian or worse. We daydreamed and did crosswords when we were students, they argue, so how can we prohibit our students, who are adults after all, from using their time in class as they deem fit?

A crossword hidden under a book is one thing. With the aid of Microsoft and Google, we have effectively put at every seat a library of magazines, a television and the opportunity for real-time side conversations and invited our students to check out whenever they find their attention wandering.

I feel especially strongly about this issue because I'm addicted to the Internet myself. I checked my e-mail at least a dozen times while writing this op-ed. I've often resolved, after a rare and liberating weekend away from e-mail, that I will wait till the end of the day to read e-mail at the office. Yet, almost as if it is beyond my control, e-mail is the first thing I check when I log on each morning. As for multitasking, I don't buy it. Attention diverted is attention diverted.

But this is all theory. How does banning laptops work in practice? My own sense has been that my class is much more engaged than recent past classes. I'm biased, I know. So I conducted an anonymous survey of my students after about six weeks -- by computer, of course.

The results were striking. About 80 percent reported that they are more engaged in class discussion when they are laptop-free. Seventy percent said that, on balance, they liked the no-laptop policy. And perhaps most surprising, 95 percent admitted that they use their laptops in class for "purposes other than taking notes, such as surfing the Web, checking e-mail, instant messaging and the like." Ninety-eight percent reported seeing fellow students do the same.

I am sure that the Internet can be a useful pedagogical tool in some settings and for some subjects. But for most classes, it is little more than an attractive nuisance. Technology has outstripped us on this one, and we need to reassess its appropriate and inappropriate role in teaching. The personal computer has revolutionized our lives, in many ways for the better. But it also threatens to take over our lives. At least for some purposes, unplugging may still be the best response.

David Cole is a professor at Georgetown University Law Center. His e-mail address iscole@law.georgetown.edu.