At the Barry Farms public swimming pool in the heart of one of the poorest sections of the District of Columbia, few people ever swim.

They can't. It's too crowded.

Instead, hundreds of children, teen-agers and a handful of adults, clad in shorts or bathing suits, their bodies glistening and their faces alight with delight, bob up and down in place for hours at a time.

It's free, it's cool and it's fun.

"I stay in the pool so much my mother hardly gets to see me," 12-year-old Maurice Richardson said yesterday. He said he spends all day at the pool.

Nearby, in the Southeast Washington project, two teen-agers go one-on-one on the public basketball court that gets hotter and softer as the day goes on. The sweat shines on their faces as they drive to the basket with catlike quickness.

"If I had some money, I'd go on a trip - maybe to Hawaii," 15-year-old Patrick Rooney said reflectively as he dribbled the basketball.

But Rooney said he doesn't have any money. So he spends his summer days playing basketball.

"I usually come out here in the morning about 11 a.m.," he said. "I pull up a sweat, then go home and eat breakfast, take a shower and lay down for awhile. Then I come back in the afternoon and play until they cut the lights at night."

Yesterday, Rooney was practicing his set shot as his friend, Tyrone Washington, looked on. Basketball is "my hobby," Rooney said.

"My mother keep telling me I'll be black before I know it [by playing in the sun]," Rooney said, laughing. "Ijust come out just to be playing, to have something to do. She asked me why don't I wait until the sun goes down. But I tell her that's when everybody's out there and I won't be able to get a court."

Rooney said he was supposed to start work on July 9 in Mayor Marion Barry's summer jobs program for youth. "They gave me a job. But they didn't tell me where I was working at. I kept calling and they said it was coming in the mail. I ain't got no job yet. I done missed two checks so far."

The 10th grader said he had planned to visit his aunt in South Carolina for the summer, but decided instead to stay in Washington and play basketball. "The last time I was there (South Carolina) was when I was small," he said.

Rooney said he doesn't take many trips. His last trip was on June 4, when his class went to King's Dominion.

Rooney's friend Washington said his parents and sister had gone on a trip to Fredericksburg, Va., this week. "They're staying in a hotel. They just went for the week. They wanted to get some rest."

He said his family usually goes to visit relatives in Georgia, but they didn't this summer because of the gasoline shortage. "There's hardly nothing to do there (in Georgia) but chase chickens."

At the swimming pool, 19-year-old Donna Butler was trying to keep track of the little neighborhood children she had brought to the pool.

"It's just something to do." she said, standing on the side of the pool. "It's a way to pass the day. The kids enjoy it and it keeps them out of trouble."

Maurice Richardson is on the Barry Farms swim team, which means he can swim beginning at 10 a.m., when the team meets for practice. They practice until about noon. Then he goes home for lunch and returns when the pool opens to the public at 1 p.m.

Youngsters splash water on each other or sit along the side of the pool all afternoon. Towels and chairs are forbidden in the pool area, so the children lie on the concrete at pool side and sunbathe.

About 5:30 p.m., the children have to leave the pool, so the adults can swim.

"Keeping cool," said Aaron Martin, a D.C. recreation employee at the pool. "That's what it is all about." CAPTION: Picture 1, Youngsters at Barry Farms public pool exultantly demonstrate one of most enjoyable ways of beating the heat in Washington; By Joel Richardson - The Washington Post; Picture 2, Some cool D.C. youngsters vie for photographer's attention at Barry Farms public swimming pool; By Joel Richardson - The Washington Post