Within moments, students were smashing windows, overturning furniture and fighting, with some trying to help the academy's security guards squelch the disturbance. Eleven students fled the campus, near the Canadian border, and bolted into the night.
Ogdensburg police officers, state troopers, St. Lawrence County sheriff's deputies and the United States Border Patrol were called in and the uprising was quickly put down. Those who escaped were rounded up, and the police arrested and jailed 12 students on rioting, assault and other charges; the academy expelled 48.
Administrators say the uprising was not a result of systemic problems in the academy but of the mixture of combustible characters in a severe disciplinary environment meant to rehabilitate teenagers who have run afoul of the law and their parents.
Jason Finlinson, 33, Ivy Ridge's director, said in an interview at the academy last month that with the expulsions, the school had shed its most troublesome residents.
Still, the violence brought more unwanted attention to an institution that, since opening three years ago, has drawn the scrutiny of state investigative agencies and attracted a loud chorus of critics, including former students who have accused the school of mistreatment.
The office of Eliot Spitzer, the New York State attorney general, is investigating whether Ivy Ridge violated state law by issuing diplomas, since it is not accredited by the state. The state police are investigating two cases involving allegations of child abuse and one case stemming from the riot.
Mr. Finlinson and other administrators say all allegations of abuse are false and the invention of disgruntled former students and competitors in the potentially lucrative industry of so-called specialty boarding schools.
Mr. Finlinson said the school was offering a valuable service for parents who feel they have run out of ways to help their children. It's also an expensive service. Tuition and fees are about $3,500 per month.
"We're in a pretty controversial industry," said Mr. Finlinson, who oversees about 500 students and a staff of about 230. "When you're trying to change people's lives, there's controversy. If I didn't want the controversy, I'd go wash cars."
Ivy Ridge comprises a cluster of nondescript brick buildings and a playing field on the campus of a former junior college overlooking the St. Lawrence River. The campus is on the outskirts of Ogdensburg, a small town set amid farmland, about 128 miles northeast of Syracuse.
Its white cinder-block hallways and classrooms are remarkably quiet, and the students - the boys, with close-cropped hair and uniforms of khaki trousers and white shirts; the girls in plaid skirts - move around the building in single file. The children, who are high school age, come from all over the country and abroad and arrive with records of drug and alcohol use, tangles with the law, truancy, domestic violence and splintered families. But they share one thing in common - parents who, at wit's end, have decided that the academy's steep tuition is a small price for a last-ditch effort to straighten out their children.
The academy is affiliated with the World Wide Association of Specialty Programs and Schools, a chain of six behavior modification programs in the United States and abroad run by a small group of businessmen in St. George, Utah. In recent years, local governments and the United States State Department have investigated allegations of physical abuse and immigration violations leveled against World Wide-affiliated programs. Affiliates in Costa Rica, the Czech Republic and Mexico closed under pressure from local authorities, and one in Western Samoa closed for "business reasons," according to James Wall, a public relations representative for World Wide.
Ivy Ridge's program, which Mr. Finlinson said was based on a plan developed by World Wide, is highly regimented and emphasizes discipline. Students try to progress through six levels based on a system of merit points. Privileges are granted at each level. Residents are not allowed to receive telephone calls from their parents until they attain Level 3, which can take several months.
The program includes an academic curriculum, though it is primarily computer-based and self-directed: students spend several hours a day in front of computers working silently on programs.
In the days after the disturbance in May, Mr. Finlinson said, a few parents withdrew their children. But he said that the school was now stable and running smoothly.
Nevertheless, his troubles - and the threat of more damage to the academy's reputation - have not disappeared.