The threat of closing hangs over a South Burlington-based residential program for teens that its advocates describe as uniquely successful. And no one knows — or will say — why it’s happening.

The board of the state-funded Allenbrook Home for Youths recently decided to shut the facility on June 30 and sell it to a private developer. Proceeds from the sale of the Allen Road property, consisting of three houses and a barn, would be used to establish a fund to help young Vermonters pay for college, the board tentatively agreed.

“This is malarkey,” Martin Macgowan, a former Allenbrook staffer, wrote in a letter he’s circulating to rally support for the program. Vermont already offers a range of financial-aid options for its college-bound residents, and Allenbrook provides “irreplaceable” services, Macgowan said in an interview.

“These youth are being kicked out of their home,” he added. “It would be irresponsible to shut it down.”

Six minors currently live at Allenbrook, which has served hundreds of young Vermonters over the past 30 years. “It’s the most community-integrated program of its kind in Vermont,” said Joelle van Lent, a consulting psychologist for Allenbrook. The teens either attend public school or work at local jobs, she noted.

Allenbrook follows the “teaching-family” model of caring for kids who no longer live with their parents and who are “struggling emotionally or behaviorally,” van Lent explained. Under this approach, a trained couple lives in a group home and models positive family interactions.

Research conducted over the past 40 years shows the teaching-family model to be highly effective, said Mike Boggs, a North Carolina-based consultant who trains couples and individuals to take on those roles. Boggs, who has worked with Allenbrook staffers for the past five years, said the proven success of the model does not hinge on any particular set of “charismatic” teachers.

At Allenbrook, Jerry McDougal and Betsy Yung served as the live-in caregivers for the past 20 years and received a national award for their work in 2005. Yung died last July, and McDougal is nearing retirement.

Yung’s death “may have had a lot to do” with the board’s move to snuff the program, Macgowan suggested. But the specific reasons for the planned shutdown remain unclear, both Macgowan and van Lent said. “Our understanding from the board is that it has to do with financial factors, but they haven’t explained that at all,” van Lent continued. State funding for the program is not in jeopardy, she said.

The causes of the action are also a mystery to Steve Dale, commissioner of the Vermont Department for Children and Families, which is providing Allenbrook with up to $1.4 million this year. “Allenbrook has been operating a great program for a long time,” Dale said, calling McDougal and Yung’s work “absolutely exceptional.” The state would like the teaching-family model to remain available in Chittenden County — there’s only one other program of this kind in Vermont — but “we’re confident that with lots of lead time we can make sure there will be good transition plans in place for the youth involved,” Dale added.

Allenbrook’s overseers are mum on the reasons for their decision. Bob Walsh resigned last month as Allenbrook’s board president, and Sherman Miles stepped down from the vice-president post at around the same time. Neither would comment on the move to close the facility.

“The board appears to be in turmoil,” Macgowan observed.

Allenbrook Treasurer Mike Keller declined to elaborate on what he described only as “a variety of reasons” for killing the program. The board will meet soon to reorganize and to “explore alternatives that have come up,” Keller added. “We’re still proceeding in the direction of a sale,” he said.