It's just after 4 a.m. and Caryn Quinn, a seventh-grade student at Cooper Intermediate in McLean, is awake, preparing to do what she does every morning at 5:45--practice figure skating.

Quinn is the 1982 U.S. Figure Skating Association's South Atlantic intermediate ladies champion and finished sixth in the Eastern U.S. Sectional early in January. It doesn't come easy.

She practices at the Mount Vernon Ice Arena until 9:15, then goes to school until 2:30 p.m. Afterward, she either skates for a few more hours or attends the Washington Ballet School on Wisconsin Avenue.

"And I'm asleep by 8, so I can get up for practice," she says. "It keeps me pretty busy."

She still finds time for her studies and other activities. Quinn is "mostly an A student," she says, and leads "mostly a normal life, compared to most of the skaters I compete against."

"Most have a tutor (for school), and they spend even more time on the skating than I do. If I was at a training center like some of them, I would be out (on the ice) all day. I do other things."

Her life, though, is hardly that of the average 12-year-old.

"At age 3, I said I would never skate," Quinn says. "At 4, I began ballet. Then when I was 8, I moved from New York to down here. A friend got me to the rink. I just started and tried it and liked it. So I started taking group lessons and then individual lessons three years ago."

She practices twice a day, five days a week, with her personal coach, Carol Ferrentino, who qualified for the national seniors five times. Quinn's goal is to make the U.S. Olympic team in 1988.

Ferrentino, who has been teaching for a decade and skated with the Ice Follies for six years, says, "She's a very quick learner. For her, it's just a matter of learning the moves. All children have the Olympic thought. If she wants it there's no reason why she can't do it.

"Temperament is her biggest attribute. And that will take her as far as she wants. Caryn's won a lot of things. She wouldn't be where she is if she wasn't talented. How good is she? Just look at her performance."

In her three years of serious skating, Quinn has won 29 competitions, including the South Atlantic Intermediate title. In that event, she received a perfect score of five ordinals--first place from each of the five judges.

"She won the freestyles and figures," Ferrentino says. "She was a solid first in everything. I don't think there's one thing she is better at. She is good on all of figure skating. But, now that she is older, the figures are more appealing."

Ferrentino began coaching Quinn three years ago. "She was skating at the rink where I was teaching, and she wasn't satisfied with her coach then," he says. "She just asked me to do it. I teach only on an individual basis. I started teaching her when I had an opening.

"As you teach, the skaters look at how your students have done. You sort of get rated by the skaters. She decided I was the coach for her."

Cost has never been a major obstacle. Caryn's father works in advertising and her mother is a part owner of the Diet Center in Potomac.

"Sure, it's expensive compared to some of the other sports kids are in," Marianne Quinn says. "We've never rented private ice time, so that keeps the expenses down. We pay for the ice about every eight weeks, so it works out to about $2 an hour. That isn't too bad. I guess with everything--two new pairs of skates each year, ice time, coaching, entry fees for competitions, travel--it runs several thousand dollars a year.

"This is about average for a skater who is serious. Many pay a lot more and some pay less. We just pay the bills when they come in."

Caryn expects to make the expense worthwhile. In addition to her Olympic aspirations, she hopes to join an ice show and eventually study sports medicine, specializing in figure skating.

"I want to become (a physician) because I had a knee injury and it took a long time for the doctors to figure out what was wrong," she says. "But for now skating is first above everything."