Young men and women in their late teens and early twenties headed to another country this summer to work unpaid to help with a community project and to learn about a different culture.

There is nothing new about that: organizations such as the Peace Corps have channeled young Americans to foreign countries for years. The difference in this case was that the young people were from Europe and the country they labored for was America.

Last Friday, after a hard day building playground equipment and pathways in Alexandria's Beach Park, seven of these European students sprawled in the city's Durant Community Center. One of the center's rooms was filled with mats and sleeping bags, backpacks and laundry. In the kitchen, Hans Moser, 21, of Switzerland, was preparing a pot of hot chili.

During dinner, the spirited conversation swung between German and English as the visiting youths talked of their impressions of America and their plans for the evening -- half were to attend a Beethoven concert, the others were off to see "The Rocky Horror Picture Show."

"This is a good opportunity to spend vacation time in America and to leave something worthwhile behind," said Sigrid Ruland, 23, of West Germany, who has been to America three times. "I know more students would be interested in working in this country if they could afford to make the trip."

The 18 Europeans who participated in the exchange program paid their own way here, but were housed and fed by the two host communities, Alexandria and Fort Collins, Colo., George Wynne of the Council for Urban Liaison explained.

Administered by the International Volunteers in Community Service, the West Germany-based program has sent European university students to work in neighboring countries for the past 15 years.

This is the first year IBG (from the original German) has ventured to America.

"It is kind of like a Peace Corps in reverse," said Wynne, whose liaison group found the two community sponsors in this country. "The students want to interact with Americans and start up international friendships. The communities learn about foreign countries and get projects done they normally wouldn't be able to afford."

Twelve European students spent the past three weeks building a park in Fort Collins.

In Alexandria, six students who have been working in Beach Park were joined recently by Kerst De Jong, 21, of Holland, who worked for several weeks in Fort Collins.

James Chasnovitz, Alexandria'a landscape architect, said the two-acre Beach Park, at Rucker and Johnston Place in the city's Rosemont section, had needed new playground equipment and drains under the soccer field for years. Neighbors had drawn up plans for the park and the City Council had budgeted some money for improvements, but the park was not one of the city's priority projects.

This spring, Chasnovitz heard about the work program from Wynne, an Alexandria resident. The City Council appropriated $9,500 for materials and about $800 for food and offered the community center on Cameron Street to the students as a shelter.

Chasnovitz said neighbors raised another $1,000 for food and IBG administrative costs.

"It really worked out well," said Chasnovitz. "The families have taken turns feeding them. They've been invited to dinner almost every night for the three weeks they've been here."

Mayor Charles E. Beatley Jr. held a barbecue for the students last week on his farm and a local car dealership provided them a van for weekend trips to the beach.

"It was a case of business and community groups coming together in a cultural exchange," said Chasnovitz, who supervised the students' work. "And we got a great park out of the deal."

Today, the students' work will be completed and Beatley will officially accept the renovated park this afternoon. Though several of the students have left, some plan to stay in this country for several more weeks.

Last week, the students spoke about their impressions of America.

Some said they were surprised by Americans who opened their homes to foreigners, a practice they said was not common in Europe. Several expressed awe at the number of disposable goods, which they said seemed wasteful. Most were frustrated that many Americans they met could not, or would not, discuss international politics.

Volker Arndt, 21, of West Germany said he thought the work program was worthwhile, but said he is still confused by Americans; he feels they have no depth, only surface gloss, because they say things they don't really mean in order to be polite.

"In Germany the people do not invite you in their homes, or always say you are welcome to come again, only if they mean it," he said. "That is nothing bad about America. It is probably very good."

Carmen Mueller, 20, also of West Germany, expressed some frustration that she had been unable to to tell Americans about the fear her fellow Europeans have of a nuclear arms race between America and the Soviet Union.

"I think many Americans my age don't know what is going on in the world, maybe because America is a big country and they are far away from other countries," she said.

Other students in the program were Urlich Braune, 18, of West Germany, and Paulo Oliveira, 18, of Portugal.

Chasnovitz called the program a success in Alexandria and said the city may host other IBG students in the future.

"People don't think of America ever being in need," he said, "but there are thousands of communities that could use a helping hand and a lot of foreign young people who seem to be willing to come all the way out here and help, just for the experience."