It's been nine years since millionaire Eugene Lang, in a spur-of-the-moment decision, promised a sixth-grade class in New York a free education. Next year, some of those students will graduate from college.

"My greatest fear is that I will have too many graduations to attend on the same day," said Lang, in the District last week for the national convention of his "I Have a Dream" Foundation.

As "his" children have grown, so has the number of philanthropists who have joined Lang. They have promised a college education to more than 9,000 children, including several hundred in the Washington area. Sponsors are expected to make an up-front commitment of at least $350,000. There are 139 projects in 40 cities.

The convention at the District's Sumner School was attended by about 250 sponsors, project coordinators, parents and a few of the "dreamers" themselves. In workshops, they discussed problems they've overcome and lessons they've learned.

An issue that surfaced often was whether the brightest children in public schools should be allowed, or encouraged, to attend private schools. Critics have warned that the Dream program could send the wrong message to inner city children if it led them to think of their communities as negative by saying the only way to succeed is to escape from their neighborhoods.

"Two of my kids were solicited for prep school," Lang said. They were leaders, role models for the group . . . . I asked, 'Would they be more effective if they remained with their peers and became leaders -- or if they left?'

"I suggested, well, maybe I encouraged them to stay," he said. "They are now among my group of kids at top colleges. Don't let the best kids be siphoned off."

But not everyone agrees.

Locally, Joseph Williams, project coordinator at Kramer Junior High School in Southeast, is elated that one of his "dreamers" will attend Holton-Arms School, a private institution in Bethesda.

"To keep her would be to limit her potential," Williams said. "I don't think you can ever take a person totally out of their environment . . . unless you uproot them from their community too. Anyway, you have to be versatile in this world. You have to learn how to survive in your community and in a universal sense, in the world as a whole."

Although the private school issue may be debated for years, some evolutionary changes have come faster.

For instance, Lang was the sole sponsor for his project and others followed his example. But now people have begun to join together to adopt classrooms. Christopher Coons, a 26-year-old law intern whose family started a project in Wilmington, Del., is an example of how the definition of sponsor has expanded.

He suggested to his family that members start a project, and several relatives donated money. "I spent one year designing my program, talking to schools, ministers, community people, letting them get a sense of owning the project," Coons said.

"The program is evolving to include a second generation of people who aren't business executives but who want to participate as sponsors," Coons said.

The projects in the Washington area are all based on the original model of individual sponsors working with a classroom of children.

The District programs started in Southeast schools, at Winston Educational Center, Kramer Junior High, Friendship Educational Center, Johnson Junior High and Frederick Douglass Junior High.

Maryland has Dream projects at Hyattsville Middle School and Seat Pleasant Elementary School.

This fall, four new programs are expected to open in District schools, Lang said. The names of the schools would not be announced until parents were notified.

The new local projects will follow the traditional model of individual sponsors, said Joan Sesnick, a spokeswoman for the foundation's headquarters in New York.

But in Hartford, a church has become a sponsor; in Iowa, a college. In Boca Raton, Fla., a group composed of 40 people, churches and organizations has promised to pay college tuition for fourth- through ninth-graders who live in a housing project. This fall, the University of Hawaii will become a sponsor to the entire third grade population of Maui.

Alice Kugelman, of Hartford, went to her church membership in 1987 with the idea that the congregation become a sponsor. The urban church, which is predominantly white, adopted a nearby elementary classroom. The class is well integrated. The school's neighborhood includes an area with the highest incidence of prostitution and drug trafficking in the city.

"It's an urban church with a large suburban, professional congregation that has a commitment to the city," said Kugelman, a self-employed antiques appraiser. "People donated money and we raised $400,000 to adopt our class."

But social differences meant it took a while for church members and "dreamers" to become comfortable with each other, said Deborah Harrison, the project coordinator.

"The first year, I and some of the 'dreamers' were uncomfortable because this is a wealthy, prestigious white church. Everyone on both sides was leary. Some mentors were afraid to go to certain areas to pick up children," she recalled.

"Now we have our ups and downs, but we hung in there and never a day has passed when I ever regreted this position or the program," she said.

Because the entire church serves as a sponsor, there is never a shortage of human resources. Kugelman said 51 members volunteer as mentors and 20 are tutors.

In Boca Raton, 40 people wanted to help children in a particular housing project rather than a particular classroom, and they set up a "Dream" program to do it. One of the 40, Marvin Zale, had a friend who was already doing some work with the children.

"We asked the foundation for advice and they said each project coordinator usually handled 50 to 60 kids so we took the fourth- through ninth-grade kids in this project -- 48 kids," Zale said.

A major challenge, he said, is to keep the children active. Some projects nationwide hold summer programs for this reason.

The problem that surprised Zale most has been teenage pregnancy. "I wasn't prepared for 14-year-olds getting pregnant," he said. "But I have children of my own and they did things that surprised me, too."

The sponsoring group has counseled pregnant teens, gotten them placed in a state-owned home where they could continue going to school, and seen that they return to public school.

Said Zale, "The program would run better if all children were perfect, but that's not the real world."