The location was elegant, the reception fixings were generous and name tags were doled out to the local and national children's advocates at the True Reformer Building on U Street NW.

But perhaps the most important guests at the recent screening of "Aging Out," a foster-care documentary, were the ones without name tags or business cards: D.C. foster children.

About 20 teenagers from group homes or living with foster parents sat in the audience and watched a film clip of three people from California and New York with lives similar to their own: youths who, after years in the foster-care system, were about to leave it because of their age.

When the lights came up, the District youths were brimming with questions: What kind of help will I receive after I turn 21 and leave the system? Will I get a check? Can the system help me get a job?

Brenda Donald Walker, director of the D.C. Child and Family Services Agency, spoke to assuage the anxiety. She said that community programs and other services exist but that the agency had to do more to make children aware of them.

Those in the D.C. foster care system remain in city custody up to age 21, making it one of the few jurisdictions in the country that by law takes care of abused and neglected residents from 18 to 21.

More than half the 2,700 District foster children are 13 and older, and 100 to 150 youths age out each year. Some have become homeless. Others have gone off to college. Nationally, about 25,000 foster children a year leave institutional care, and the results in that population are also mixed.

For youths who have spent years in foster care, where every need from food to money to a place to live was the responsibility of the government, it can be a distressing shock to be out on their own.

"Aging out is kind of a reverse birthing process," Walker said after the movie. "This time, the umbilical cord is cut after the child is grown, but in so many cases, still not ready to live independently."

Judith Sandalow, executive director of the Children's Law Center, which represents hundreds of abused, neglected and special-needs children, said she was troubled by the kinds of questions the foster children asked. The nonprofit group arranged the screening with WETA-TV and the Public Welfare Foundation, and the movie was funded by the Jim Casey Youth Opportunities Initiative, a national nonprofit group focused on preparing foster youth for independence.

"The program proved that foster youth don't believe that they are getting help or that there is anyone helping them to learn to be independent adults," Sandalow said. "The kids had never heard of any of the programs, and I wonder if any of them even existed."

What happens to children once they leave foster care depends largely on what kind of help they received while in the system, such as parenting workshops for young mothers and life-skills courses on presenting a resume or opening a bank account.

Walker has put together a youth advisory committee of agency officials and community groups to tackle the issue. But at a recent meeting, the panel's members reviewed a list of children who would age out in the next few months.

Some of the children on the list had left the system months ago, and no one at the agency knew where they were living or how they were doing. Walker told the group she was not pleased. "For those who are out, we need to find out," she said.