At 18, Dana Brick says she is old.

For the Class of '86, said Brick, the fun is over.

Late night parties, shopping sprees, weekends at the beach are kaput, finished. Next on life's agenda: college, studying, working and making money.

Brick graduated from Oakton High School Monday night in an emotional ceremony at George Mason University's Patriot Center arena. The guest speaker, Judith Garcia, a Fairfax County teacher who was one of 10 finalists in NASA's teacher in space program, told the 582 graduates that having friends is one of the most important measures of success.

"Today . . . is the beginning of your adult life," said Garcia. "The course of your lives will be guided by decisions you make. There are opportunities not only here on earth, but in outer space. Nothing means much at all if you have to do it alone."

But Brick and her friends say they already feel like adults plunged into the serious matters of life. "We kids feel like, you know, 'I'm going to college, my parents are paying all this money and I want to get good grades for them, for me.' I keep saying to myself, 'Five years from now you're going to wish you were still in high school,' " said Brick, with a sigh. "I think a lot of kids will be in shock about what happens when they get home from [high school] graduation."

There will be no shock for Brick. She plans to attend Wheaton College, a small Christian school in Wheaton, Ill., where she will study music, with hopes of pursuing a career as a professional singer and songwriter.

Most of her friends are going to state colleges and universities in Virginia. Said Brick: "It's kind of the thing to do. The kids feel that if you don't go to college, you're really a nobody . . . a bum. I'm a lot more laid-back than most of my friends. I don't go with society. I know what makes me happy, and it's not necessarily what the majority of people define as happiness."

She stopped running for Oakton High School's track team last winter because "it was getting harder and harder for me to be quick . . . and also the pressure. The pressure of my senior year, the pressure of a couple of colleges sending scouts to watch me. I didn't like that."

Money, popularity, sororities and status are not important to Brick. The Oakton student body recently named her "Best All Around" in the high school, but she said the award was frivolous: "It's just a popularity contest."

Brick blushes at any mention of her awards and is uncomfortable with the image of being a socialite. Religion, helping needy people, writing music, playing the piano and maintaining control despite the pressures of growing up are what's important to the attractive young woman.

"It's hard to have really good friends . . . a lot of people look up to me but don't look at me as their friend," said Brick. "People look at me as a perfectionist. I've run all three years in high school and this year I burned out and everybody noticed. It's when I make a mistake that I get hit hard. It's like I'm not supposed to make a mistake . . . . That puts a lot of pressure on me and it's one of the reasons I want to go far away. Where no one knows me."

Music is her "number one thing" now. Her summer plans include work at a discount department store and a nearby nursing home, perhaps a visit to Wheaton College, jogging, reading and "just hanging around."

"I'm saving up enough to get an electric piano to take to college," said Brick. Her favorite song is "Straight Ahead," by gospel rock singer Amy Grant.

"It has a lot to do with my situation," said Brick, her sparkling blue-green eyes peeking out from behind dark, luxurious lashes. "The song tells about the future and how right now it feels really strange to know that you have to go on with your life."

Brick's mother Lynda said she is puzzled by the somber attitude of her daughter's generation.

"I've watched it with kids in senior high . . . they have the weight of the world on their shoulders," said Lynda Brick. "The kids worry whether they're going to be alive 10 years from now."

Next week is "beach week" and most of Brick's friends are taking a break from worrying and heading for Ocean City, Md. However, Brick, who said community service is one of her greatest joys and hobbies, is going to West Virginia to help flood victims rebuild their houses and repair their fields.

"My goals are set more toward my own understanding of life," Brick said. "I'm really independent. My happiness is more a peacefulness."

But once the graduation speeches were over Monday, the night was like all the other final hours of high school.

Solemn mood shifted to rowdy party as students tossed an inflatable beach ball, blew soap bubbles and hooted and howled while school administrators gave the graduates their diplomas. Some even hugged and kissed school principal Laura Thomas.

"They're [the students] being tame tonight," said a school guidance counselor, as she watched the scene from the side.