The pen is not only mightier - it's also simpler, more gracious

The written word can be a handy way to exert power, and to do it with a gentle touch - at home or in organizations. For instance, when your children's friends invade your home, do you feel helpless? Are there times when you want to get a message across to them without seeming unfriendly - without having your offspring caught in the middle, embarrassed, and unhappy? I've found the written word can do the job in an impersonal, but still warmhearted, way.

I learned this when our 16-year-old came home from a Saturday evening gathering of friends. She was highly amused by the way her host had signs taped up all over his house. His parents were not home, and he wasn't up to coping with a mess or with parental dismay. So, with hand-lettered signs, he had let the group know which snacks could be eaten, which left untouched; which bathroom to use, which rooms were out of bounds, and such. The young people loved it and made a few signs of their own for kicks.

I took note.

As in most communities, youngsters here follow their elders in smoking and beer-drinking, regardless of the legal-age restrictions. And remembering the social pressure on me at that age, I wanted to offer a retreat from it, along with a convenient excuse for not simply following the crowd. Since I couldn't see myself spending time or energy as a self-appointed snoop, I preferred to trust their sense of fairness as guests.

So with some bright cardboard and an inexpensive frame to make it seem semiofficial, I made a sign. In halting calligraphy I wrote: We enjoy sharing our home with you . . . But we have to abide by laws. It is illegal for kids under 18 to drink or use drugs (except tobacco). As long as you are here we are responsible and legally liable if you get in trouble. Please do not put us in a bad position with your parents or the law. . . . The Management

(And The Management really doesn't like our guests to breathe tobacco smoke.)

Both my daughter and her older brother approved. Hospitality never lapsed. Their friends continue to be our friends.

I was still radiating the glow of success when I was appointed chairman of the house committee for a local organization. From that vantage point, the members suddenly seemed as irresponsible as my daughter's teen-age friends. As a longtime member, mostly along for the ride, I hadn't been aware of the tedious details of the job. Now I found myself leaving notes to cover all sorts of annoying and costly problems.

But I'd learned that there are notes that have the sound of music and others, the rasp of discord. I aimed for short, sweet, neat ones that would solve problems without adding irritations. Just above the doorknob on each exit, for example, I posted this: A reminder - last one out: thermostat, lights, double-lock. Thanks.

They were only calling-card size, penned on self-stick shelf paper and spray-coated to seal out dirt and dampness. (They could have been typed.) Three years and two committee chairmen later, similar notes are pouring oil on troubled waters. Such messages, hastily scrawled and stuck up with torn tape, can look angry and temporary - not encouraging cooperation.

I had been left another written-word problem solver by my prior chairman. But his was not in leaving but in receiving notes. To encourage cooperation and to pacify members, he needed sensible, responsible messages, instead of second- and third-hand reports and rumors of breakdowns and oversights. So he used a simple clipboard with a pad of lined paper and a pencil on a string. Directions on it said: You can help the House Committee. Please note whatever needs our attention, with your name and the date. We'll get to it as soon as possible.

The notes were regularly checked and initialed by the chairmen and problems handled in a convenient, peaceful manner. Membership participation has been warm and patient.

We learn from each other. First from the party boy, then from the other chairman.

Now, following my success, my daughter has started leaving her own style of notes. On the dining table: ''I need my calculator for class tonight. Please leave it here for me.'' No accusations. Neat. Done with felt ink markers like a greeting card, embellished with butterflies and flowers. And now that she's off across the country, I've discovered she has left little notes behind on her dresser, in her closet - all bright and cheerful, just like her: Use whatever you want but don't change the hems - unless you change them back.