Waterloo Elementary School's nearly 20-year-old magnet program for seriously emotionally disabled children could be dismantled as early as next year, as school officials struggle to find the best way to meet those students' needs.

The highly praised program's uncertain fate comes at a time when some parents say the school lacks staff to deal with its 13 percent enrollment of emotionally disabled students -- the highest percentage among county elementary schools.

"We just want our numbers to be handled," says Cathi Hill Morrison, Waterloo PTA president. "What we're doing now is treading water, and it's a shame for the kids."

Waterloo has the only program in the county providing specialized services for elementary school students with serious emotional disabilities.

The school has a full-time psychologist, a crisis intervention counselor and a guidance counselor to deal with those students.

In the 1993-1994 school year, Waterloo had 31 emotionally disabled students, nearly half of all such elementary school students in the county, and a 50 percent increase from the year before.

In the past school year, Waterloo's overall enrollment dropped from 600 to about 300 students. Students with severe emotional disabilities made up 20 percent of the fourth grade and 25 percent of the fifth grade.

The rising enrollment of emotionally disabled youngsters brought complaints as those students graduated from self-contained classrooms into regular classes.

Parents of students in regular classrooms complain of emotionally troubled students who have locked themselves in the bathroom for as long as three hours while, they said, teachers and administrators bided their time, waiting for them to come out.

They also cite frequent disruptions that have wasted academic time as teachers diverted their attention to calm down the disabled students.

"These kids with behavioral difficulties, they really give us some additional challenges," said Sandra Marx, special education director. Her office is exploring such alternatives as opening a second magnet center to lower Waterloo's numbers and dismantling the program entirely, sending all students back to their neighborhood schools. A decision is expected after systemwide redistricting is completed, as early as March 1995.

In theory, Waterloo is supposed to be a way station for emotionally disabled students, who receive intensive services in self-contained rooms, are integrated into regular classes and eventually sent back to their neighborhood schools.

But some parents like Waterloo's program so much they want to keep their children there. They praise the school's teachers and administrators, all of whom have received training to deal with such students.

Vicki Werner said that her son used to hurl chairs and use abusive language at his home school. His teachers feared upsetting him and recommended that he go to Waterloo. "I was " greatly opposed to having my son move to Waterloo," she said. "But I've certainly changed my mind."

The school has changed her son's behavior -- "given him a reason to care," she said. "He cares more about himself. And he's beginning to care about others."

Parents of Waterloo students without such disabilities say they support the program but worry that their children suffer because of the high enrollment of such students.

At a PTA-sponsored town hall meeting this month, more than two dozen parents turned out to complain to school board candidates and other officials about the disruptions that they say are caused by the school's emotionally disabled students.

The parents argued that the school system should open a second regional center to reduce the proportion of special education students at Waterloo. They also wanted those students' test scores to be recorded at the students' neighborhood schools, not at Waterloo.

"I think what we want for the children is a fair chance for them to succeed," Mrs. Morrison says.

Karen Allen, another parent of a general education student, said that inadequate staffing hurts the emotionally disabled students well.

"We are not against inclusion," Mrs. Allen says. "We feel for the benefit of all the children, whether they are special or general education, that we must have adequate staffing until the program is reduced."

Even some parents of emotionally disabled children recognize the constraints the school is under. "I think, as the number of special education students increases and the staff doesn't change, it would validate the [the other parents'] concerns," said Diane Lillis, whose son, Aaron, has dyslexia and emotional disabilities. "These children need a lot of support to be mainstreamed into general classrooms."

Educators such as Peter Leone, head of the University of Maryland's Center for the Study of Troubling Behavior, say that Waterloo should not be the only school with the responsibility of teaching students with serious emotional disabilities.

"If I was a parent, I wouldn't want my kids to be bused down across the county," he said. "I think other schools need to develop the capacity to serve those kids. They need to share the responsibility and to develop the expertise to serve those kids."

But he said that Waterloo "really appears to help kids learn to adapt and adjust to the everyday demands of the public school environment . . . They individualize for all students, not just those who are identified as special education students."

"The bottom line is, the state and Howard County are saving money and at the same time, providing a much higher level of education for the kids than they would be at a much larger institution somewhere else," he said.

There is no standard in the state as to what a school's population of special education students should be, though the state and national average is 12 percent to 13 percent, according to school officials.

And some top educators say it doesn't matter how many students at a school have serious emotional problems. More important are the resources available to help those children, including adequate staffing and support services.

"It's the services and how well the support services manage the number and, at the same time, ensure the high quality of education," said Richard Steinke, assistant state superintendent of special education. "Where you have a larger [number of students], you must have requisite resources available."