Two Northern Virginia youths--Fort Hunt High School freshman Jennifer Gordon and Annandale High School freshman Glen Kwok -- represented the U.S. this summer at Bulgaria's third International Children's Assembly, a group of young musicians from all over the world.

The youths were among about 200 children from more than 100 countries whose travel and expenses were paid by the Bulgarian government. They were chosen by the Bulgarian Embassy here to take part in the Assembly.

Jennifer, 15, and Glen, 14, arrived at Sofia, the capital city, in August, greeted by throngs of local children carrying flowers, gifts and requests for addresses.

Both are violinists in the Northern Virginia Youth Orchestra. Glen has studied the instrument since he was 3 years old; Jennifer spent the early summer months at the Juilliard School of Music camp in New York. They were two of only 10 violinists at the Assembly. The other musicians there played an assortment of instruments, including many from Third World countries that the youths had never seen. Jennifer called them "funny instruments."

The Assembly, established during the United Nations' International Year of the Child, includes a multitude of "gifted and talented children up to the age of 15," said Eugheni Kirilov of the Bulgarian Embassy. "Since 1979, countries have donated over 18,000 poems and art works from children around the world -- it is like an international treasure for us."

Poets, dancers, musicians and artists were called upon to perform as soon as their planes landed. Also included in the Assembly were students in technical fields, such as mathematics and computers, Kirilov said.

"We were given about five minutes to write a short speech," said Glen, "and then we taped it for television."

For the first week, the pair performed daily on the radio and at concerts. They also were among the few selected to play in the grand concert at the end, in Sofia's new opera house. They chose Antonio Vivaldi's "Concerto in A Minor for Two Violins," a piece they had played together before, "because we didn't get too much chance to practice while we were there," said Glen.

The trip was a busy one. The pair, along with their American escort, Associate Professor Ronald Slaby of Harvard, and a Bulgarian interpreter, spent their days performing. In the evenings, the Bulgarians entertained them: "They had Donald Duck puppets."

Their nights were spent talking to other youths. There were "500 participants, if you include all the escorts and interpreters and Bulgarian children" staying at local college dormitories. Outside stood the police, "so we wouldn't get lost -- we were guarded everywhere we went."

For the last three days, the participants piled into 20 buses and traveled in two motorcades around the country. Said Jennifer: "There were seven police cars in front and seven in back; we got to go through all the red lights!"

They stopped at various villages and memorials around the country where children were lined up to greet them. The warmth of their hosts made an impression on the American youths: When asked what they liked most about the trip, they both said "the people." As Jennifer put it, "I really liked their attitude -- they were never nasty or anything."

They described children from the Soviet bloc country as "much warmer and friendlier than kids in the U.S."

"Many of them spoke English," said Glen, "and we learned the essentials in Bulgarian -- thank you, please, I'm sorry, and Jennifer's favorite, ice cream."

Glen also had an opportunity to use his fledgling French with fellow musicians from Switzerland, and both students made what they call "lasting pen pals" from Sri Lanka and Canada.

The Bulgarian children's feeling for the participants apparently is mutual. Said Kirilov, "A film documentary was made of the first Assembly, and I remember at the end, when the chidren were lining up to leave, the Bulgarian children who acted as hosts started to cry. Here they'd only known these international children for a few days, but they were so sad to see them go.

"It was really very touching."