SITES LIKE VirtualRatings.com cannot help but attract extremists. VirtualRatings, a Web site that allows college students across the nation to review their professors on-line, prides itself on two basic policies. The first is its lack of anonymity - all comments must have e-mail addresses attached to them - and the second is the value of its service, which is to provide a forum for students to evaluate and compare their professors.

Despite these high aims, however, it seems far more satisfying for students to use a site like VirtualRatings to rant about professors they've disliked or wax emotional about ones that they've adored than to offer thoughtful, constructive criticism that will be helpful to others.

And what's to keep professors from reacting unethically to these comments by favoring or targeting students based on their comments?

Such bashing of professors has long been a favorite pastime of students, and VirtualRatings will be no different. Most students, however, are fully aware of this tendency in their peers (as well as themselves), which may finally prevent them from taking VirtualRatings seriously. Students simply know better than to base meaningful academic decisions on comments posted on the Web by Joe Student.

In this context, it is irrelevant whether these comments have an e-mail address attached to them or not because a name does not tell students anything valuable about the evaluator.

And as for contacting the evaluator to learn more, it is simply wishful thinking to assume that students will opt for e-mailing people they don't know to follow up on Web postings over the much more reliable method of asking people they trust or shopping classes to see for themselves.

Given this predictable reaction from many college students, it seems fitting to ask exactly what larger purpose this site will serve in the long run, if any at all.

Students' VirtualRatings evaluations of professors, no matter how flattering or disparaging, are unlikely to result in much hiring or firing where it matters. Only the most naïve among us would honestly see a Stanford administrator surfing the Web and making any sort of faculty decisions, good or bad, based on his or her findings at VirtualRatings.

Furthermore, as soon as one broadens the focus to include schools across the U.S., VirtualRatings becomes an admissions officer's nightmare.

How many admissions officers will have to answer for some student's comments on this professor or that, and how helpful can that possibly be for prospective students, who may or may not have reacted the same way to a given professor?

Admittedly, if one considers that postings from a wide range of schools are available at the click of a button, VirtualRatings may well have excellent potential as a comparison tool for prospective students and parents.

However, once one factors in the likelihood of exaggeration, the lack of any prior knowledge of the evaluator and the wide variability of students' opinions on any given subject, one is only left with a moderately interesting site with a real information value akin to that of Loveline.

VirtualRatings is novel and it's fun, but the appeal ends there. Students, like all other human beings, rarely pass up a chance to be disgruntled, but, if VirtualRatings is that chance, it cannot also be a valuable tool for evaluation, comparison and change.

If students want to offer constructive criticism, or even if they just want to criticize, they would do better to take some time filling out formal class evaluation and sharing their thoughts directly with professors.

After all, professorss are much better able to act on students' suggestions if they don't have to search for them on the Web in an endless stream of other, undoubetly somewhat less than constructive, comments.