Dae Ki Ko, a 6-year-old Korean-born first-grader at Glencarlyn Elementary School in Arlington, told his mother he felt "alone" in his new life in the Northern Virginia suburbs.To cheer him up, she invited two dozen of his classmates to a party for her son.

On the big day, two children appeared at the Ko house.

"Dae was so sad. It was so hard for him to understand what happened," said a friend of the family, San Ja Kim, who works as a resource aide at Glencarlyn.

"These foreign-born children feel like perfect idiots when they know they are not. They feel so isolated and alone."

Shunted in and out of school systems as jobs and apartments become available to their families, more than 12,000 children in the Washington area struggle, as Dae does, with the pressures of coping with a new language and a new culture.

Confronted with the daily task of obtaining a basic education in a language they often cannot read or understand, the children of these new immigrants often face bitter emotional adjustments and peer pressure.

According to educators and administrators in Washington area schools, these problems are compounded by the double-edged goal of many of their parents. They want their offspring to succeed in the English speaking world, and at the same time hold on to their former cultures.

'We want them to know how to get along here," said Omid Omidwar, an Iranian student at George Washington university whose children attend Arlington schools. "We want them to learn, but we don't want them to foget our ways."

Thao Phuong Bui, a Vietnamese student at Wakefield High School in Arlington who lives with her aunt, said she and her sisters and brothers are not permitted to speak English in the house.

"She doesn't want me to forget Vietnamese," Bui said. "But I'll learn [English] somehow, I'll get along. We all will somehow."

Drawn by the chance for a fresh start or forced here by political or economic difficulties at home, the variety of foreigh-born families who have flocked to the Washington area is great.

In Arlington, where almost one in five students is foreign-born, the majority come from Vietnam, Korea and Latin America. The District attracts a large number of Caribbean islanders and Iranians, school officials say.

Fairfax County, which has 2,100 students for whom English is a new language, can currently count 56 foreign tongues among its student population. The job of teaching English to these students falls to the area's schools, which carry on amid debate about the methods and goals of their programs.

More than 9,000 children who have a less-than-marginal knowledge of English are funneled into special high-intensity English training programs.

Developed and run at a cost of more than $3.5 million, the courses, most commonly called English for Speakers of Other Languages (ESOL), isolate students in small groups for 30 minutes to an hour each day dor instruction in English, in reading and in comprehension.

Beyond that, Arlington-where 19 percent of the student population is foreign-born, the highest in the area-offers a small number of students bilingual instruction at the elementary and intermediate levels.

In these classes, students receive up to 40 percent of their class work in their native language-Korean, Vietnamese or Spanish. When they have learned enough English, they move on to regular classrooms.

A persistent critic of the bilingual approach has been Arlington County Board member Walter Frankland, who calls the program "wasteful," "counterproductive" and "ridiculous."

"Children may have a 6-month period of adjustment but we should accept that, we shouldn't cater to that need," Frankland said.

Defenders of the program, including many parents, disagree.

"We know at least 10 percent of our elementary age children should be in a bilingual class," said Marie Shiels-Djouadi, an Arlington curriculum specialist. "Sometimes they can barely function in a regular classroom. What do we do with them if they don't understand?"

Instead of expanding the bilingual program, Shiels-Djouadi has developed specialized English training for 120 junior and senior high school students. The pupils follow a day-long schedule of English comprehension and reading classes, and must complete these classes before entering regularly scheduled classroom activities.

But Bui, the Vietnamese student at Wakefield who is in the program, complains that she has little opportunity to speak her newly learned English.

Bui said she sees her American counterparts only in the hallways between periods, in physical education or at lunch. "But at lunch, Spanish eat with Spanish, Vietnamese eat with Vietnamese," said the 17-year-old.

Other students who have enough competency in English to be enrolled in regular high school classes share Bui's sense of isolation.

"I don't know if it's because of me or because of them," said Patricia Rodiriguez, who emigrated to this country with her family two years ago from Colombia. "But it is hard to get along with the kids here."

In contrast with Arlington, Fairfax County relies on ESOL classes and a small number of aides fluent in the languages used most often in the school system.

"We have had students from 73 different languages-now 56 or so-at one time," said William J. Burkholder, who directes the country's ESOL programs. Burkholder said Fairfax school administrators "feel strongly" about avoiding the bilingual approach.

Meanwhile, difficulties persist despite the schools' efforts.

Foreign-born students and parents "don't understand the relationship to teachers here," said Lilian Falk, who works in ESOL programs in Prince George's County schools.

"Their backgrounds are neither PTA-oriented nor after-school oriented. And they just don't understand the permissiveness in our schools. It all takes a bit of getting used to." CAPTION: Picture 1, Patricia Rodriguez, has experienced the isolation language problems impose. By John McDonnell-The Washington Post; Picture 2, But classes try to remedy students' incorrect usage; Picture 3, Arlington teacher Insook Won uses posters to help Korean-born students. Photos by James M. Thresher-The Washington Post