Bryce Quayle is among the top seniors at Walt Whitman High School in Bethesda, but he considers himself "a long shot" among the 47 members of his class who hope to be admitted to Yale University this week.

The problem, says Quayle, whose extracurricular activities include Boy Scouts, the debate team and Junior Achievement, is "low" grades and "low" test scores. He says he "only" has a 3.37 grade point average (a B) and combined math and verbal SAT scores of 1250 of a possible total of 1600 on the college entrance exam.

"Maybe they need someone to bring their averages down," joked Quayle, who already has been admitted to Johns Hopkins University. "But I'd have more confidence if I had a 3.7 average."

For Quayle and thousands of high school seniors across the country, it's that time of year again, a time of obsession with the mail carrier's punctuality and whether envelopes from colleges they've applied to are thick--implying acceptance--or thin.

At Whitman, ranked among the top 10 academic high schools in the country, students are particularly obsessed with whether they were admitted to Ivy League schools and other prestigious colleges. Those schools received more than 300 applications from the school's 500-member senior class this year.

Whitman students reached their peak of college admissions panic yesterday, because most Ivy League schools mailed acceptance and rejection notices at 12:01 a.m. last Friday.

In the Whitman cafeteria yesterday, students talked of little else. Yale, they said, is this year's clear favorite, "artsy-craftsy but with academic integrity." Harvard, by contrast, with 31 applicants who have roughly a 1-in-6 chance of getting in, is slipping in popularity and has the reputation for being "snobby and boring." Princeton, with 36 Whitman prospects, is thought of as "too robotic and too academic."

Getting into an Ivy League school "is definitely a status thing here," says Whitman counselor John Keating, who wrote 85 recommendations this year. "But we try to prevent it from getting into runaway gear."

Some Whitman students received hints about their standing early. A student waiting to hear from Harvard found the university's course bulletin in the mail last Saturday, although a certificate of admission--embossed with the Harvard and Radcliffe college seals and bearing the student's name in calligraphy--did not come until noon yesterday.

A few lucky others heard months ago. Shari Finkelstein, 17, knew in December that she would go to Harvard in the fall. Finkelstein, who scored 1510 on her SATs and has a 4.0 GPA, filled out an early-admissions application in November. She had to write six essays--on topics including what is important to her, why Harvard should accept her, and which non-academic activities she would pursue once she arrived in Cambridge. She also had to list all the books she had read in the past year.

Despite her academic qualifications, Finkelstein had some doubts about whether she would get in. "I worried that I didn't have enough extracurricular activities," she said, even though she is an accomplished ballerina.

Kurt Hirsch, who until yesterday hadn't heard from some of his schools, gobbled down pizza, Jell-O and chocolate milk before rushing home to learn his fate. He found thick envelopes from Harvard and Princeton, and two letters of congratulations from the Princeton Club of Washington, including one from four U.S senators who are alumni.

At Whitman, the crush to get into prestigious colleges is legendary. Last year, 505 students applied to 342 colleges in 40 states and four foreign countries, according to career counselor Jan Petrasek. Seven of 39 applicants got into Harvard (and all of them went) and 10 of 36 into Yale.

Petrasek says that 1983 "is our best year ever for MIT"--five of nine applicants were admitted--and also for Maryland, which drew 214 applications from Whitman students, partly she says, because of the economy. Petrasek said her office sent out 2,400 transcripts this year, including 27 for one student.

Most Whitman students have visited campuses and heard through the grapevine what is required to gain admission to the schools they want to attend. Few students applied to Amherst College this year, for example, after Whitman went 0 for 11 last year.