YOU CAN'T JUDGE a college by what they say in those catalogs," observed Darryl Gwyn, a 16-year-old senior at Paint Branch High in Burtsonville, Md., to his fellow passangers as they sped south along I-85 toward North Carolina. Gwyn and seven other high school students had crammed themselves, their suitcases and their bedrolls into a rented Plymouth van for a weekend tour of several colleges, including Duke and the University of North Carolina. There they would meet with admissions officials, students, and generally, they hope, get a taste of what college life is like.

The trip, which cost each student $135, was set up by Campus Explorations, a Bethesda-based organization that since last year has taken about 150 high school students on 10 tours of colleges. Campus Explorations was started by Lila Segal and Sue Weintraub, who say they were inspired by their own children's experiences with the college-selection process.

Campus Expolorations aims to relieve parents of the added expense and time of going with their teen-agers to visit schools and also to relieve teen-agers of what can be a hindrance -- having parents around when they are trying to find out about campus life from college students.

The students in the van came from an assortment of backgrounds and schools, both private and public. For all, the trip was a chance not only to visit colleges, but to share their doubts, ambitions and hopes. Some seemed certain of the careers they would pursue. Others were vague and worried by their own indecisiveness. For some the pressure from parents to get into a "good" school appeared to be both subtle and intense, and all seemed aware of stiff competition from other students.

They all saw the trip as a chance to talk with undergraduates about academic loads, social life, dorm food -- and to envision themselves as college students. But during the trip, some began to feel they had boarded a roller coaster ride of hope and despair that will not end until April, when colleges send out notices of acceptance -- and rejection.

Autumn reds and golds whiz by in a blur as Sue Weintraub steers the van south. The students' rush of inquireies to establish what acquaintances they have in common has abated. Bob Lefebvre, 17, a senior at Wootton High in Rockveill, has pulled out an orange folder and is agonizing over an essay assignment ("Write a carefully planned, fully developed composition . . . ") on Robert Browning's poem, "My Las Duchess."

Darryl Gwyn is munching vanilla sandwich cookies and outlining some well-developed ambitions. "My goal in life is to live happily, comfortably, with a minimum of pressure, not worrying about how I'm going to meet the next bill, where I'm going to be living, if I'm going to be out on the street next week."

Thus, he says, he will go into medicine. "As a doctor, you have reasonable security because there's always got to be a doctor somewhere . . . Also there's the thought of being a doctor -- wearing a white coat -- what do you call that? Prestige? oIf you're going to go out for something, why not shoot for the top, become a doctor or lawyer, be one of the big people?"

Gwyn, the only black student on the trip, says he will apply to at least seven colleges, includng Harvard, Johns Hopkins and Duke. His choices have nothing to do with their location or social activities, but rest on one criterion: "They have the best record for getting students into top medical schools." Social life doesn't matter, he says. "You can have a good social life anywhere."

Kear Martin, 17, a junior at St. Andrews Episcopal School in Bethesda, says he "hasn't the foggiest" where he will apply. "My main criterion right ow is being near a beach . . . just as long as it's away from snow. I'd like to go somewhere in California, but my mom's not to hot on California. She says California's not ready for me."

LeFebvre says that after college he will "probably just get into business or something like that . . . I keep putting off applying. I can't make my decision . . . I want to go somewhere I can have fun -- I want to learn, but I want to enjoy it."

Inevitably, the subject of SAT scores arises

One girl: I got 650 in verbal (section) and blew it on math."

Another: "I got 550 in math and 550 in verbal."

First girl: "I got 550 in math."

Second: "That's blowing it?"

First: "For me, it is."

Rachel Cohen, a 17-year-old senior at Winston Churchill High in Potomac, says her heart is set on Duke. Because she's heard is has a good psychology department -- she wants to be a child psychologist -- and a good social atmosphere.

But she says because she spent more time on high school extracurricular activities' than on getting top grades, "I'm a borderline case to get in." She adds, however, "It's good to have done activities -- it looks like you do something more than just Study."

Of the seniors at Churchill, she added, "Everyone's concerned about going to college," she said. "Once we got our class ranks people said, "Forget it, I'm going to (the University of) Maryland."

Kathleen Hogan, a 16-year-old senior from Walter Johnson High in Bethesda, laments, "There are supposed to be 375 valedictorians applying to Notre Dame. There's no way that I'm going to get in. . . . My only hope is that my dad went there. They say 20 to 25 percent of the freshman class is children of alumni."

Darryl: "Some colleges have 14,000 applicants -- how can they remember you."

Rachel: "I think they put [pictures of students] in a hat and say, 'she has blue eyes, that's good; she looks good in that cheerleading outfit; he's president of the chess club, so we'll take him.'"

Kathleen: "You have to do something to make yourself stand out. I went to a seminar on writing the college (admissions) essay today, and someone said, 'Write it in a poem.'"

Around 10:30 p.m. the van arrives at the deserted Duke undergraduate admissions office. Taped to the door are messages telling students which Duke undergraduates they are to stay with that night.

Bob hefts his bedroll from the van and says with a nervous laugh, "We're going to walk into some room and say, "Hi, I'm some pipsqueak from high school."

The next morning, after all-you-can-eat grits, French toast and lukewarm eggs in a Duke cafeteria, the students assemble for the offical campus tour.

Some are bleary-eyed from unofficial tours with their Duke hosts the night before. A few attended a fraternity's "bozo hat party," a gathering of strange or hilarious hats.

Others tell tales of a night in "C.I." (Cambridge Inn), the Duke beer joint, where they played a game called "quarters" in which people try to flip quarters into cups of beer. If they miss, the have to drink the beer. One student gripes that the college kids kept changing the rules on him, forcing him to down more than his share.

Kear says one student he stayed with was up all night studying for a test. "Every now and then I'd wake up and hear him turning pages." He adds, "I didn't eat breakfast. I barely made it in time. I had no will to get up -- I had no will to survive."

In the admissions office, Patsy Bennett of the alumni division tells the students that about 1,300 to 9,100 applicants each year are accepted. Duke receives more applications from Washington D.C. and Montgomery County than from other areas of the country, she says but Duke sets no quotas on admissions from those areas.

Bennett downplays the significance of SAT scores, saying that only after essays, activities, grades and recommendations are evaluated do "we plug in the test scores."

"Nobody's asked about cost," says Bennett, "and that's probably just as well." Tuition, including room and board, personal expenses and books and supplies, she says is $8,100 a year.

The students join about 15 other people, including other prospective Duke students and their parents, for the campus tour led by Duke junior Kathy Conway. As they walk along, one girl confides in another "I don't know if I could get in here. I have a 3.65 grade-point average, but no AP (Aadvanced Placement) courses." She steals glances at passing college students, many clad in navy blue Duke sweaters and jackets. "There are all these other people your age here. That's neat; I'd really like that. But first I've got to get in somewhere."

Another girl says with downcast eyes, "I'd like to go here, but it's a hard school, and I'm only an average student."

As the group rounds the corner onto the main quad in front of the student union, a woman selling tickets at a table calls out to them, "Come on, you don't want to walk around on campus, Find out what Duke is really like. Come see You're a Good Man Charlie Brown.'"

Rachel: "Yea, the real Duke -- CI, bozo hat parties. But seriously, you guys, they're doing a lot of homework. One girl I was talking to will have a three-hour history final. It's a month and a half away and she's already studing for it. She hasn't even gotten all the material yet -- how can she be studying for it?"

After a 20-minute ride to UNC, the group is met by Stephen Cohen, a senior who leads them on a tour of the Chapel Hill campus.

"What are you interested in?" he asks.

Darryl: "Getting in."

Kear: "Girls"

After a whirlwind tour -- students activities center gym, the libraries and many construction projects ("This is a dangerous campus," says Bob under a crane), the Pine Room cafeteria (the Swine Room" Cohen tells them), the students gather with about 150 other people in a lecture hall to hear Dick Cahswell, director of UNC admissions, tell students that he is "not that concerned about SAT" scores but that "if your high school record looks like the national debt, you're going to have some problems."

He adds, "I tell my son, who's a senior in high school, 'Go anywhere you want to but go where you'll be happy. If you're not happy, you won't learn as well.'"

Cashwell adds that there are about 5,000 applications for the 480 spaces reserved for out-of-state students.

One student notes, "He really does discourage us from applying."

Victoria Lee Anthony, a 16-year-old senior at the Maret School in Northwest Washington, reflects on the trip after returning home. "I want to go to Duke, and if I'm not accepted, my heart will be broken and I might not enjoy next year as much." An adviser, she says, "told me Duke would be my longest shot. But I really did love it there."

Victoria adds that this is the first time a major decision affecting her life is so totally in the hands of strangers. "We really can't do anything about getting in. It's totally up to them. It makes me feel very insecure. I'm doubting myself now, wondering if my grades were good enough and if I should have tried harder."

Of the seniors she knows, she says, "We're all very nervous, all very scared."