In many ways, 1954 was a year to remember. Moviegoers flocked to "On the Waterfront," "The Caine Mutiny" and "Rear Window." A new car cost less than $2,000, and gasoline that cost 29 cents a gallon filled the tank up for a drive. A new home could be purchased for $22,000. Dwight D. Eisenhower was in the White House, and the U.S. Supreme Court outlawed segregated schools with its landmark ruling in Brown v. Board of Education.

That fall, Annandale High School opened its doors to 1,000 students in the eighth through 11th grades who were transferred from crowded Fairfax and Mount Vernon high schools. Taking their cue from an Eisenhower speech called "Atoms for Peace," the students voted to call themselves the Atoms.

Much has changed over the years, but Annandale High students are still called the Atoms, and the school on Medford Drive is now the oldest one in Fairfax County still in its original location, although it has grown four times over with additions and renovations.

Those who made up the first student body are now gray-haired grandparents. Both the school and Annandale have undergone equally dramatic transformations in the past half-century.

Any 50th anniversary is an occasion to celebrate, to reflect on slow, evolutionary changes that seem as if they happened in the blink of an eye. Last weekend, alumni, faculty and current students gathered at Annandale High to reminisce about the school and what it has meant in their lives.

No matter what decade it was when they attended, graduates agreed they had acquired a solid education and a wealth of treasured memories during their years inside the red brick building. But many were struck by the differences between the early years and today.

In halls where ceramic tiles the color of Key lime pie have been coated with gray paint, in the gymnasiums where the wood floor is decorated with the school symbol, a red and white atom, and in meeting rooms and auditoriums named for past principals, graduates recalled a school whose history follows the course of the world around it.

When it was born in the segregated 1950s, the school's all-white student body lived in a fairly rural area. The school was roiled by the social upheaval of the 1960s and '70s, then struggled with ethnic tensions in the 1980s that came to a head in the 1990s. During the last two decades, Annandale High has developed into a school that is often held up as a model of diversity, with students who trace their roots to more than 80 countries.

"Whatever happened in the community was here in the school," said James G. Finch, Annandale High's principal from 1966 to 1986. "That's still true. The school is a mirror of the community."

At its beginning, the school reflected a country at the dawn of a nuclear age, before anybody worried about things like spent fuel rods. When Eisenhower gave his "Atoms for Peace" speech before the United Nations, his words resonated even in the then-bucolic countryside of Annandale.

"It was Pleasantville," said Tony Bardo, a 1970 graduate whose musical group, the Fabulous Dialtones, played classic rock at one of the four "proms" held Saturday night.

As the first principal, Ralph E. Buckley's task was to forge a school identity and spirit among students, many of whom had already attended other high schools. So a contest was held to come up with a school nickname.

Initially, "the Atoms" was running a poor second, recalled Buckley, who stayed in the job for 12 years. The sports director had already chosen red and white as the school colors, since they were the only combination not already spoken for among schools in its athletic class. The favored nickname among students was the Red Devils.

But in an era when a blessing was said in the cafeteria before lunch, the Red Devils were not to be.

"The kids wanted it," said Buckley. "But a Baptist preacher in the area called in and complained, so it was removed from the list."

So Atoms it was, entirely fitting in a town where every sign at its border announced, "Welcome to Annandale. Town of the Future."

The school needed an alma mater as well. Music teacher Fred Wygal sat down in his office one day and wrote the words. They were only supposed to be temporary, he recalled, so the school choir would have something to sing on stage and inspire students to compose their own words. But the verses were printed in the first addition of the A-Blast, the student newspaper, and stuck.

At the time, Annandale was so undeveloped that Wygal penned this refrain after looking out his window: "Amid the meadow and the tree, our school will proudly stand."

"It was a cow pasture," he said. "There was a huge tree in the back, and big, wide-open expanse."

The building itself bore little resemblance to the school now attended by some 2,500 students.

"There was no gym, no cafeteria, no auditorium, no library and no lockers," Wygal said. "It was one long, straight hallway one-eighth of a mile long."

Many of the earliest students remember being thrilled at the prospect of going to a brand new school where they got to make the traditions.

"We called ourselves the Atoms and Eves," said Nikki Hunter McDonald, an eighth-grader in 1954 who, at her 40th reunion, hooked up with the fellow she had had a crush on, Bill McDonald. They married two years ago, and invited Buckley and his wife to the wedding.

The landmark Brown v. Board of Education ruling the spring before Annandale High opened had no effect on the student body's makeup. The all-white school reflected the town's demographics. At the time, it seemed like diversity to have foreign exchange students from Germany, France and Switzerland. It would be the mid-1970s before the first African American student attended.

Today's diversity is as striking to those first students as their era's homogeneity is to present-day students. Hunter McDonald, who drove a school bus for 33 years, recalls the time an Annandale High student of Indian heritage boarded the bus and noticed Hunter McDonald's class yearbook, which she was carrying to prepare for the 40th reunion.

After thumbing through the photographs, Hunter McDonald recalls, the student said in utter amazement, "You all look alike. You're all Caucasian."

These days, said Finch, the school's second principal, whose tenure included the end of a dress code that had barred girls from wearing pants, "this community is a United Nations. When I walked around the school, I saw all these kids, all nice and polite, and all different nationalities."

A vast demographic change began in the 1980s, when immigrants began arriving in large numbers, said G. Raymond Watson Jr., principal from 1986 to 1994. It took awhile for school officials to recognize the tensions between various ethnic groups, he said.

"We thought that our wide-open arms and good intentions were enough," he said. "We didn't realize we had to be proactive in getting students involved."

After a particularly ugly confrontation in 1993 in which one student shot another, the school introduced a program of peer mediation, training students to lead conversations with other students.

"It was the dedication of the staff, and the kids buying into it, and the community supporting it that made it work," said Donald L. Clausen, Watson's successor as principal from 1994 to 2003.

Many of the alumni credit the principals with the effort's success.

"When I was here, there were just a handful of Oriental students and blacks," said Mike Cavalero, a member of the Class of 1968 whose wife graduated from Annandale High in 1972 and whose two sons graduated in 1999 and 2002. "Now it's like a U.N. It runs the whole gamut. I was amazed and pleased at how well integrated it is. Everybody has gotten along. Don Clausen developed a real spirit of inclusiveness."

Geoffrey Jospitre, 14 and treasurer of the current freshman class, said he felt some alumni were staring at him and two other African American students in class last week, which he interpreted as their astonishment that the student body is no longer all white. He said diversity extends to courses as well as nationalities and race -- many boys take cooking classes, and girls take sports marketing.

Most of the current students consider the ethnic tensions of their predecessors as outmoded and as hard to fathom as prayer in the cafeteria.

"A lot of my friends are other nationalities," said Donald Martin, an 18-year-old senior, as he sat in the stands singing along to a Simon and Garfunkel tune played by the Fabulous Dialtones. "It doesn't matter what your race or background is. It's your views. The school may look different. But the people and the goals are still the same. Everyone comes here wanting to make friends, learn and be successful."