"This is a vital, burgeoning school and we're going to exist somewhere," declared the energetic director of the Washington International School, Dorothy Goodman.

She wants the school to continue to exist at Tregaron, the site it has leased from the Davies heirs for several years. She regards the threat of the sale and possible development of the site into a housing project as a knife aimed at her heart.

The Washington International School is a unique institution, and it grew largely out of the spirit and dedication of this one woman, who with the help of friends begain it in 1966 with three children in the basement of a church.

"It was all part of the Wilsonian dream, the educational aims of the League of Nations," said Goodman, an historian by training, in describing the context out of which her idea for the school grew. "We're real missionaries."

The mission, as she explains it, is to break down the destructive and narrow aspects of nationalism and to bring together children from all over the world.

As the school grew it spread to other church basements. Then a Ford Foundation grant enabled it to buy a large building in Georgetown, which is still used for the lower grades. In 1972 it leased Tregaron for the upper grades through high school.

The school now has about 500 children from 76 countries, half of them Americans born here - and a good number of these are inner-city children supported by scholarships. Children attend classes taught in French or Spanish one day and English the next.

The teaching staff, largely the wives of officers in international organizations here, are paid minimal salaries.

The school has developed close ties with its neighbors in Cleveland Park and Woodley Park, and in the current crisis has circulated leaflets asking neighbors to sign guarantees on a loan that would enable the school to buy the property.

According to the leaflets, the school has available about $1.6 million in cash, committed pledges and a loan of $600,000 from the Ford Foundation. In addition, "The school may need to obtain between $1.5 and $2 million from a commercial lender." The guarantees from parents, neighbors and friends to help secure such a loan have now reached more than $500,000, school officers said.

Goodman herself has lived in Cleveland Park for 20 years and said she remembers the early days of the school when she used to stand on the back deck of her house, looking out over the area. "I used to say, 'Someday we're going to have the International School at Tregaron.'"

The school is there now. Whether it will stay there remains to be seen.