It was one of those sunny, near-perfect Saturday mornings, when thoughts are supposed to be light and activities leisurely. But in a packed room at Prince George's Community College, a group of 30 American and Soviet children sat together and discussed a dark and chilling subject: the threat of nuclear war.

"Are you as afraid of nuclear war as we are?" asked Kim Norris, 12, a pupil in the Prince George's County schools.

"Maybe even more afraid," said Irene Pavlov, 14, the daughter of a Soviet diplomat. "You haven't had a war on your territory in many, many years. We had one 40 years ago. We know what war is like. We hate war."

The 15 American children are members of the county schools' talented and gifted program. The 15 Russian children, whose parents are journalists and diplomats, attend the Soviet Embassy school. They were brought together yesterday as part of a three-week program sponsored by the community college to focus on the nuclear arms issue.

"I deal a lot with fears that children have," said Miffi Bedrick, a school guidance counselor and an organizer of the event. "All the other problems I hear about -- divorce, or 'Other kids are picking on me,' or 'My teacher doesn't like me' -- are minor beside their greatest fear. Their big fear is the fear of nuclear war."

While the need for peace and the disaster of war dominated the two-hour question-and-answer period, the children, who all spoke English and dressed alike in jeans and sweaters, managed to satisfy some of their curiosity about the others' lives. Occasionally, the Soviet children, in particular, managed to insert a little of their personal and national philosophies into the discussion.

"What do you think of America?" asked one Prince George's pupil.

"America is a good country," replied Dmitry Domakhin, 12, whose father is a diplomat. "There are so many beautiful monuments and museums and things. I've been here four years, and I like it. It's such a pity that it's a capitalist country."

Dmitry grinned as the audience of parents and pupils laughed.

Later, he posed his own question to the American children. "In the Soviet Union, when we have lunch at school, the lunch is free," he said. "I just want to know, how much do you have to pay?" Ninety to 95 cents per meal was the answer. Dmitry smiled again.

Alexei Palladin, 14, whose father is a correspondent for the Soviet newspaper Izvestia, pointed out that the Soviet Union and the United States have been friends before.

"What do you know about the Second World War?" Alexei asked the Americans. No answer. He nodded as if that was what he expected.

"Nobody even knows," he said, "that we were allies. We were fighting Nazism together. We're remembering that war because we lost 22 million people. We want you to know that we were friends then, and we can be friends now."

Alexei sat down to hearty applause.

The gathering was not all talk. The Soviet pupils, wearing the self-conscious grins of all children forced to perform, sang several songs. Two girls played a piano duet. A tiny ballerina danced in a narrow space bordered by folding chairs and camera cables.

The American pupils bashfully declined to perform.

Afterward, the children were invited to contribute to the "Peace Ribbon," a seven-mile-long strip of peace slogans that will encircle the Pentagon in August to mark the 40th anniversary of the bombings of Hiroshima and Nagasaki.

As the meeting ended, Dmitry, chewing cookies and drinking hot chocolate, offered his assessment of the morning: "I don't think there's really much difference in us," he said with a shrug. "We're just kids."