It's a modest proposal: Turn off your television for a week.

But for many Americans, it is sure to sound like a radical idea. And that's the problem.

If going without television for seven days seems like a disruptive notion, then the sponsors of the upcoming ''National TV-Turnoff Week'' really are making an important point.

Incessant TV watching may be similar to other substance abuse: People who feel that they can't do without it for very long are probably addicted.

The national effort to prod Americans away from their TV sets from April 24 to April 30 is coming from a broad-based coalition, ranging from the Children's Defense Fund to the American Medical Association to the PTA.

A group called TV-Free America is organizing the no-television-for-a-week project. Its board of advisers includes novelist Barbara Kingsolver, environmentalist David Brower, poet Wendall Berry and media critics such as Jerry Mander, Mark Crispin Miller and Neil Postman.

Executive Director Henry Labalme says that ''this campaign represents a significant departure from the stale debate about program content and the endlessly unsuccessful attempts to improve the quality of television.''

In other words, don't hold your breath for the networks to clean up this nation's TV mess. And keep in mind that there is another option besides continuing to consume it.

For many of us, walking into a room and seeing a blank TV screen prompts an insistent invitation -- even a demand -- that amounts to: Turn it on and keep it on.

The National TV-Turnoff Week may not make a dent in longstanding TV addiction. But as the April 24 kickoff day approaches, there are signs of significant momentum.

Already, at least 3,000 schools nationwide -- with more than a million students -- have opted for formal participation during the last week of this month. ''Pledge cards'' are being distributed to students, encouraging them to swear off the tube for that week -- and to fill in blanks with what they plan to do instead.

The president of the District of Columbia's Congress of Parents and Teachers has high hopes for the endeavor. Thriftone Jones predicts it will ''help us all realize how much richer and more productive life can be without a universal time-filler that all too often overwhelms more productive, active and rewarding forms of learning: reading, writing, thinking, doing.''

Well said. This TV-zoned-out nation needs a jolt out of its passive lethargy. The basic message from television to viewers is to not do much of anything -- other than go out and buy things.

Organizers of National TV-Turnoff Week cite some grim statistics:

Two-thirds of Americans ''regularly watch television while eating dinner.''

In the average U.S. home, TV is on for seven hours a day.

When asked whether they'd rather watch television or spend time with their fathers, 54 percent of kids between ages 4 and 6 said they'd rather be with TV than dad.

On the average, a child sees 20,000 commercials in a year. By age 18, a person has seen 200,000 violent acts on TV, including tens of thousands of murders.

Quite a few TV viewers are not complacent about their habit. Many would like to kick it. One survey found that 49 percent of Americans say they watch too much television. (And 73 percent of parents express a desire to limit their children's TV watching.)

National TV-Turnoff Week provides an opportunity to turn vague desires into action. And the healthy impacts could extend beyond the mental and emotional to the physical.

Television, points out Michael F. Jacobson of the Center for Science in the Public Interest, ''keeps us firmly planted in our chairs, often with food firmly planted in our mouths.'' And, he warns, ''television will become more alluring as TV sets get bigger and sharper, receive hundreds of channels and are hooked into computers.''

Often, complaints about media seem to have no more effect than gripes about the weather. But here's something you can do: Mark April 24-30 on your calendar as a TV-free week in your household. And if you want to spread the word, pass this column along to friends, neighbors and co-workers. You might even want to contact the TV-Free America office (http://www.tvturnoff.org) for an organizing kit.

The lives you improve may include your own.