Marilyn and Gerald Elprin thought they had found the ideal place to raise a family when they moved to the "new town" of Columbia in 1969.

Not only did they view themselves as part of a grand experiment in suburban living, but Howard County's newest community was picture perfect: an oasis of shade trees and broad, quiet streets.

Best of all, the couple noted, their children would one day walk across the street to a brand new elementary school. That tranquil picture changed last December when the County Board of Education voted to close Faulkner Ridge Elementary, which the Elprins' three young children and 300 other neighborhood youngsters attended. Columbia, whose phenomenal growth once made school closings unthinkable, had at last become the victim of declining student enrollments.

"I will always be angry and bitter at the way this particular school closing was handled," said Marilyn Elprin, who with 15 other parents filed a suit against the school board to keep Faulkner Ridge open.

In voting to close Faulkner Ridge later this month, the school board ignored a staff recommendation to shut down a smaller Columbia school, as well as the wishes of the Faulkner Ridge community, said Elprin, the school's PTA president. "The concerns of this community were simply not considered," she said. "You had a school that was only 14 years old, with one of the highest enrollments in the county. And that's the one they decided to close. Where is the sense in that?"

Officials in Howard's education department and school board members said the closing of Faulkner Ridge and Rockland Elementary, an older school in the county's northeast corner, will disperse enough students to keep other, smaller schools from closing.

"Closing Faulkner Ridge was a judgment call, a close call," said school board member Stan Salett, one of three members who voted for the closings on Dec. 16. Two board members, including current chairman James Murphy, voted against closing Faulkner Ridge.

"There was no overwhelming case for closing Faulkner Ridge or Longfellow," the school whose closing was recommended by department staff, Salett said. "It was the most difficult decision I ever had to make . . . . It came down to the comparable impact on the two neighborhoods."

The two school closings come at a time when elementary school enrollments in the predominantly rural county as a whole are increasing again after a decline of several years, educators say. Earlier this spring, students in kindergarten through fifth grade numbered 9,571 county-wide. Officials expect 9,760 to be enrolled this fall, 11,860 by 1992.

Nevertheless, the experts say, Wilde Lake and other Columbia West neighborhoods will not enjoy the dramatic growth that will swell schools on the east side of Columbia and other areas where development is under way. By 1989, the Columbia West region will have only 51 students more than it had in the fall of 1982, said Maurice Kalen, the leading program planner for Howard schools.

"We've been one of the few counties in the state that has been able to avoid school closings," Kalen said. In the future, however, "the real issue may be whether to close schools or maintain them and hope the numbers turn in the right direction."

If school closings are an unpleasant novelty in Howard, they are old hat to Montgomery and Prince George's counties, which have shut down dozens of schools over the past six years. By 1986, Prince George's will have closed 65 schools, more than 40 of them elementary facilities; Montgomery expects to have closed 47 elementary, 10 middle level, and two high schools by 1985, spokesmen said.

"Maybe we've been over-fortunate," Salett said. "Our enrollments have stayed at a fairly even level: first, rapid growth, then a slight dip, and maybe a turnaround by 1990." The school board, bracing for sharp decreases in the number of teen-age students, already is contemplating middle school closings and redistricting.

In Columbia, where two of every five Howard residents live, parents say they are reluctant to gamble on schools remaining open when the climate seems to favor the opposite.

"There is absolutely no guarantee that once you send your kid to a school, that school will not be shut down and your child will have to be transferred," said Manuel Antonakas, a neighbor of Elprin's whose family was one of the original 400 who settled Columbia in 1968.

When the school board voted to close Faulkner Ridge, Antonakas sought a promise from officials that his 6-year-old daughter could complete elementary school at Running Brook--the new school for Faulkner Ridge students.

"But I couldn't get that guarantee," said Antonakas, who promptly took his daughter, Joy, out of the public school system and enrolled her in Trinity School, a 375-student Catholic academy northwest of Columbia. Antonakas said his wife will probably take a part-time job to help pay Trinity's $1,300 tuition.

"I'll be darned if I'm going to let my daughter be played as a pawn," he said. "At Trinity, she'll get the one thing she wouldn't have in the public schools: stability."

Marilyn Elprin, meanwhile, is hoping that the Maryland Court of Special Appeals will order Faulkner Ridge reopened by this fall. A Howard County Circuit Court judge refused to consider the suit, and the State Board of Education has affirmed the local board's vote.

Howard officials are confident the school closings will be upheld, they said.

"We are proceeding as if the school will stay closed," said Elprin. "Faulkner Ridge was an excellent school, a place for our kids to grow up. All we want is for our neighborhood to have its own school. We thought that's what Columbia was about."