Like so many parents with offspring between the ages of 17 and 21, I'm going through several adjustments that the holiday season seems to bring into sharp focus.

In the past three years, two of our three daughters have entered college. And while I have grown accustomed to their being away, the fact that I sent away two teen-agers who have come back home as budding women has forced me to make several adjustments.

Naturally, when my elder daughters are home, I shop differently. While I've never had the luxury of speeding through the supermarket express lane, my groceries typically fill four bags. When the two older daughters join their younger sibling, the four bags quickly become eight. To make matters worse, they have further developed their individual tastes -- one likes tofu while the other likes pastrami. The third has taken to reading labels for ingredients and won't let me buy anything unless it contains natural foods.

They even have opinions now about the way I live my life and look. "Mom, your hair is too short!" says one. "Haven't you gained a little weight?" sighs the other. Perhaps I would not have taken them so seriously when they were children, but, because they are budding women, I hang onto their every word.

Sometimes the energy these young women generate can be a bit much. They seem to make the house shake each time they shut the door. "I'm here," one shouts. "Whose at home?" another calls. Squeals become commonplace at 1 in the morning. Jumping, dancing, laughing -- they seem never to get tired.

Contacts with their friends are, of course, paramount and occur at all hours of the day and night. One night, I arrived home about 11:30 to find one daughter waiting to be picked up by friends. Although they were two hours overdue, she felt the night was still ahead of her. I calmly shook my head and went to bed.

Three years ago, they might have received phone calls from as far away as suburban Maryland. Now, phone calls come in from Rhode Island, Minnesota and New Jersey -- to my chagrin and on my phone, Ma Bell and divestiture notwithstanding. When I point out they have left their college friends only days before and will soon see them again, their answer is to protest that the calls are short, always made after 11 p.m, and will be paid for by them.

Fat chance.

Of course my children, like most children, have no sense of what things cost. The budget that I barely manage to keep in check with rigid discipline goes totally out of control when they return home. I shovel out money for haircuts each claims is unavailable at school, for books, stockings, train fare and pants -- some of which are things I would like to buy for myself.

Because budding young women don't like to travel by Metrorail or bus, and heaven forbid they should walk long distances like we used to, the car is permanently commandeered by this trio of motorphiles and my new role is to coordinate drivers and chart destinations, a job so complex that I need a Commodore computer to keep track.

Their presence forces me to contrast the past with the present. Four years ago, when the eldest was 17, I had her leave the telephone number as she trekked off to a party. Now I don't try to set needless curfews or urge her to eat a balanced meal. I look for those precious moments when she wants to talk, then seize the time and make the effort to really listen. Now, I'm learning their signals to sense when they need attention or when their self esteem needs a boost.

As the nest empties, I'm also learning to let go -- an adjustment that is not always smooth. I still listen in the wee hours for their keys in the lock -- whether they are studying or partying into the night.

And I sense that all of us are going through a maturing process. While they are straddling a line between being girls and young women, I realize that this last visit was not only between a mother and her daughters but between women at different stages of their lives.

Suddenly, they are gone. And while I truly look forward to having a respite from full-time parenting and the tension of being caught between holding on and letting go, right now I can hardly wait to see them again at Christmas, with the chaos, happiness and growth that they will bring.