Thousands of District children who need mental health services are not getting them, and the city’s complex system relies too heavily on institutionalizing and medicating those who do receive care, according to a report issued this week by a leading advocacy group.

Released less than three months after the District settled a four-decade-old class-action lawsuit, the report from the Children’s Law Center calls for routine mental health screenings in pediatricians’ offices, more school-based treatment programs and other measures to make it easier for children to access services.

“It’s not the Mideast peace crisis,” said Judith Sandalow, the CLC’s executive director and an editor of the report, in an interview with The Washington Post editorial board last week. “It’s a solvable problem.”

Sandalow estimated that close to 5,000 children — or about 5.5 percent of District children on Medicaid, the population most in need of mental health services — do not have access to the treatment they need.

She said the end of Dixon v. Gray, filed in 1974, offers “a lot of opportunity” for positive change.

City officials did not disagree with the report’s findings.

“It’s consistent with the way we want the District to go,” said Stephen T. Baron, director of the city’s Department of Mental Health. Baron blames decades of mismanagement for the slow pace of reform.

“It takes time to move a whole, big system,” Baron said.

The CLC pointed to the case of a District teenager to illustrate roadblocks to treatment.

At about age 7, James Ulmer received a diagnosis of schizophrenia after he threatened his mother, Bessie Ulmer, with a knife. In an interview at the CLC, Bessie Ulmer remembered feeling “nervous and scared” when she drove her son to Children’s National Medical Center, where he was treated for a week in the psychiatric unit.

“I couldn’t take it no more,” she said. “I needed to see a doctor.”

The hospital referred the family to the CLC, which helped James obtain medication and counseling. He’s now stable and earning A’s and B’s in school.

Still, the road to recovery has been rocky. Although James showed aggression before the incident with the knife, it took an explicit, violent threat before he received a diagnosis and was treated. And the initial treatment was not in his home or community, but in a hospital. His mother said that without the intervention of the CLC, he might have never found a school that meets his needs.

“We meet kids all the time that should not come to us” for help gaining access to care, Sandalow said.

Some progress has been made, Baron said. He pointed to a 17 percent increase in the number of children served by the Department of Mental Health and a 46 percent decrease in children in residential centers, both in the past year.

David A. Catania (I-At Large), chairman of the D.C. Council’s Committee on Health, defended the city’s efforts and questioned whether the CLC report offers anything new. In his view, legislation passed after a multiple shooting on South Capitol Street in 2010 already made important changes, such as expanding school-based mental health care.

“You can’t show me a jurisdiction that invests more in mental health than the District,” said Catania, who is skeptical of further spending. “It’s a chorus of complaints with no solution but more money.”

The CLC report recommended that the city restructure the managed-care organizations responsible for providing treatment so that the same amount of money can serve more children.

“It does not take more money. . . . It requires the [managed-care organizations] to do their jobs,” Sandalow said.