Choking on spam: hazardous and offensive e-mail threatens every district. (the online edge).

A K-12 teacher in Missouri recently posted the following note to MOREnet, the state-sponsored online network that links every school district: "I am getting a huge amount of spam, some from pornographic sites. I only use this e-mail for school purposes, so I'm guessing it's from one of the Web sites I've gone to. Is anyone else having this problem?"

The replies she received confirmed that unwanted, objectionable and offensive e-mail, called spam, is indeed a growing school problem. In fact, nationally the volume of junk e-mail increased eightfold in little more than a year, and the online security firm MessageLabs (www.messagelabs.com) estimates that spam comprises 17 percent of all e-mail.

While spammers have long irritated Internet users with unsolicited pitches for reducing debt, getting cheaper mortgages, growing hair, losing weight, and enhancing physical attributes for males and females, it is now common to receive salacious content and images. As a result, Ken Royal, Webmaster of the Head O' Meadow School in Newtown, Conn., says, "I make it a point never to open email in front of students, since too many unwanted surprises can happen." But the students are also receiving spam themselves. Spam wastes time and resources for everyone, and multiplied across districts, spam can overload and dose down school servers.

HOW WE GET ON SPAM LISTS Although it is commonly believed that spammers can not grab e-mail addresses from the Web sites you visit, you may be known by codes kept in "cookies" on your hard drive until your e-mail address is revealed-such as filling out an online form, entering a chat-room, or registering for a contest-when the codes can be matched with who you really are. Spammers can then send messages related to your online behaviors. For example, if you access specific health information, you may be bombarded with pitches for medicines, medical treatments and insurance.

But it is far more common for spammers to harvest e-mail addresses from public places that include online subscriber lists, discussion groups, e-mail directories, and "crawler" pro grams that collect addresses from Web sites. Address lists are also bought and sold throughout the world, and the longer you use the same e-mail address, the more spam you'll receive.

SEEKING SOLUTIONS There is no single solution to the problem. So far two dozen states have passed controlling legislation--such as tagging spam with "ADV" making it easier to filter--and federal measures are being considered. For example, since spammers typically conceal their identities, there are proposals requiring messages to include legitimate addresses and phone numbers. But at the same time, many feel that restricting unsolicited e-mail can muzzle First Amendment rights to socially valuable information, including political statements.

The latest versions of online services such as AOL and MSN offer new filtering features, and numerous anti-spam software products are available such as Brightmail (www.brightmail.com), SpamWeasel (www.mailgate.com), and SpamNet (www.cloudmark.com). But it is also important to establish appropriate district policies such as not putting staff e-mail addresses on school Web sites. Here are additional tips to consider:

* Never reply to spam or ask to be removed from a list. This only confirms e-mail addresses and leads to more spam.

* Avoid clicking to Web sites listed in spam messages, so actions can be tracked.

* Never register with "no spam" sites or services.

* If sites require e-mail addresses for entry, try bogus addresses such as [e-mail].

* Establish a "private" e-mail address for use exclusively with friends and colleagues.

* Read privacy policies before signing up for anything. For more information, see Fight Spam on the Internet (spare.abuse.net), the Network Abuse Clearinghouse (www.abuse.net), and the SpamCon Foundation (www. spamcon.org).

Odvard Egil Dyrli, [e-mail], is senior editor and emeritus professor of education at the University of Connecticut.