In the mornings, before the dew has disappeared from the grass, the old men gather on the bench under the shade tree just outside the tennis courts at Turkey Thicket playground. At their feet lie their gym bags, plump with tennis rackets, tennis balls and enough fresh towels to last the day.

The men, most of them retirees, come early every morning, before the children arrive to trample on the old red fire engine or scamper across the 10 acres of land and before city workers come at 9 a.m to unlock the door to the recreation center at the playground at 10th Street and Michigan Avenue NE in Brookland.

On a typical day at Turkey Thicket the surrounding middle-class neighborhood lends its children to play on swings and climb jungle gyms, sends its parents with their babies to sandboxes and pathways, and pushes its residents to watch the elderly tennis players on the courts. Like the community, the playground usually is quiet. Children, dressed in matching shorts sets, whisper their arguments and seldom fight.

On Friday all of the city's playgrounds wind down, shifting from long summer days packed with activities to shorter fall schedules, during which children's games begin after school and end about 9 p.m. Already, the pace at the city's 107 playgrounds is changing: Fewer children are showing up for games, and athletic camps, clinics and sports leagues are ending.

But the men will keep coming to Turkey Thicket to play tennis, laugh and tell a few lies under the "learning" tree until the courts are too slick for the soles of their shoes.

It is the tradition of the eight tennis courts, the bench and the knowledge exchanged under the tree that sets this playground apart.

"Everyone knows you can come here any time of the day and find someone to hit balls with you," said Dick Redmond, a retired federal government employe who some at the courts refer to as "the Godfather."

"We have players who are doctors, lawyers, teachers, police officers and ne'er-do-wells," Redmond said, laughing. "We have a number of people who we haven't figured out what they do. They're too young to retire, but they manage to come every day and they all have the expensive tennis equipment."

Newcomers or novice players generally play on the northernmost courts, the ones farthest from the tree and bench, away from the critical eyes and tongues of the older players.

"We're a close-knit group," said Ken Morgan, a recently retired federal government worker who commutes from Hyattsville to Turkey Thicket each morning for tennis. "Usually on weekends, everybody comes and brings their chair and some beer. We sit under the tree. That's where history . . . and judgments are made."

"A person can sit on the bench and analyze your game," offered Al Wiley, one of the younger players and a District police officer. "This is where your opponent finds out about your weak backhand."

While the men, and a few women who have become regulars (but never visit the bench or the tree) play tennis, the children straggle in to play their favorite games. The unescorted ones come early after their parents go to work or in the early afternoon, after most of the cartoons and their favorite programs have run on television. The neighborhood is breathing life into the playground.

The nearby streets are lined with well-kept row houses, sturdy old brick apartments or frame houses with large porches. It's a clean, quiet neighborhood of middle-class families, small children and teen-agers.

"This is a neighborhood where parents take their kids places," said Mike Ragland, one of the recreation center's special consultants. "I had a hard time keeping my baseball team together. I see new kids just about every day -- some returning home, some visiting."

For each person, there's a favorite reason for going to Turkey Thicket. On one recent morning, 35-year-old Lois Yankowski walked to the park from her house, just across 10th Street, to practice skating on one of the asphalt areas of the playground.

"I just started skating a couple of weeks ago, or I should say I just started skating again," said Yankowski, who would return to the park later to push her 2-year-old daughter Julia on a swing. "I love this park. It would be perfect if it had a swimming pool."

Ruth Rhodes retreated to the park with her 5-year-old grandson Montrell Smith.

"He dug a hole under the porch yesterday and his grandfather said he was going to spank him with his cane," said Rhodes. "I said I'd bring him over here and let him work out some of his energy."

She sat on a bench under a shade tree with a piece of rope doubled in one hand, eyeing Montrell while he dug tunnels through the sand in the large wooden sandbox.

Nearby, a little girl and a boy sat on one bar of a jungle gym while another boy sat on a bar in front of them, pretending to drive a car.

"Varoom, varoom!" he said, his hands circling fiercely as he tried to command the vehicle until the obviously bored male back-seater said: "Let me drive to McDonald's."

While they played outside, 11-year-old Stephen Green sat inside the activity room of the recreation center, strumming his guitar.

"I've been coming here a couple of days," he said. "I live in Richardson, Tex., but I'm traveling with my father for the summer.

"He comes over here to play tennis," Stephen said. "I come to play checkers, Life, Monopoly. Mostly, I've been attracting a crowd playing my guitar. I like to play Jimi Hendrix, or sometimes I make up something as I go along."

By midday there were more children in the park and they had tired of playing on the two slides, the swings, the jungle gym, a cannon, and even the fire engine. They also had tired of all the board games and drawing. Ragland lined them up for outside games, as he does each day.

He piled three mats on top of each other outside the center. The 15 children lined up about 12 feet from the mats, then each ran and somersaulted, flipped, or tumbled across the pile.

Later, at the edge of the park, doors previously closed at nearby houses opened as neighbors returned home from work, and people sat chatting on porches. An elderly couple fast-walked through the park. Owners walked their dogs. Still later, neighborhood teen-agers began congregating at the fire truck.

Across the street, Joe Walden sat on the steps of his apartment building and shook his head, disgusted at the noise he said darkness brings to the park.

"It's not noisy during the day," he said. "It's the teen-agers at night. Last night one of them turned that big trash can upside down."

But his neighbor, Chris Warden, isn't disturbed by noise.

"I like living across from the park," she said. "I play in it sometimes, swing, or play Frisbee. The only thing that bothers me is when people park up and down here and I can't find a space."

At the park, everything had changed and nothing had changed. The hot sun dimmed. The organized children's games ended, but children still played. A couple sat on a bench watching their little girl in the sandbox. Two soccer teams played on one field. A few elderly men still sat on their bench by the tennis courts.