The van was driving over the Potomac River from the District to Wolf Trap Farm Park in Fairfax County when one of the 11 children aboard looked out the window at the river and said, "Ooh, look at the swimming pool."

The child had never seen a river, said Kathy Hartman, director of Kidspace, a day-care center for homeless children in the District's Shaw neighborhood.

Hartman and the children were heading for a daylong celebration in the sun at Wolf Trap, where they were among 1,000 children who had come from shelters, transitional housing and recreation centers in the District, Montgomery County, Arlington County and Alexandria.

The event was sponsored by Christmas for the Homeless, a group created by restaurateurs in 1986 that throws annual Christmas parties for homeless families.

As Hartman and her children walked down a dirt path from the hot blacktop parking lot, over a wooden bridge and under a thick shade, Hartman held the hand of one child, who held the hand of another who pointed off to a creek. "We're walking through the woods," Hartman said.

Both children, tiny and excited, asked: "What's the woods?"

Hartman explained it meant they were in the middle of many trees.

"It will be a very memorable experience for them, for them to be able to roll in the grass, for them to be able to run without walls holding them in," Hartman said. "Our play area is all walled off for security reasons back at the church."

For young children, particularly those growing up in no place to call home, it's important to have an escape from that world and slip into a different one that some people take for granted, said the Rev. John Myslinski, a member of the board of Christmas for the Homeless.

"It's really important the children be saved before it's too late," said Karen Shannon, president of the board. "This is Christmas in July."

The children sat on rows of wooden benches in an amphitheater in a clearing in the woods. They listened to "Country Current," a Navy Band. They listened to the Blue Sky Puppets and the story of Rufus, a dog with a red nose who taught them that being different is special. Former Washington Redskins player Larry Brown was there. The children sang with Fran Beatty and Friends. And danced with KanKoran, West African Dancers, who invited the children on stage to dance to an African beat.

Shamika Fairchild, 10, who came from Washington Square Day Care, a center for children from public housing in Gaithersburg, pointed at one of the dancers. "I want to be like her when I grow up," Shamika said.

"When children see good things, it gives them a sense of hope that one day they will be able," said Anna Ciuraru, director of Washington Square Day Care. "When they don't see, they don't have anything to hope for."

Tasha Wynn, 5, in a blue and white jumper, white stockings and black shiny shoes, with purple, blue, green barrettes holding her braids, looked at the puppet show.

"I like it," she said. "It's really pretty. I haven't been here before. I didn't ever see puppets."

Annette Terry, director of the Before and After program at Turner Elementary School on Alabama Avenue and Stanton Road SE, said that the children will absorb the day, the culture, the experience and take it back with them.

"They will return to the center and try some of the things they saw today. They'll remember that song and sing it on the bus," she said. "We won't leave anything here. We will take everything back."