Thousands of Los Angeles children returned to their neighborhood schools today, the first time that a court-ordered busing scheme has been dismantled in a major U.S. city school system that still contains substantial numbers of white pupils.

Despite a weekend of dizzying courtroom shifts that often left parents and school administrators bewildered, the return of about 7,000 pupils to their predominantly white schools appeared to go smoothly. Another 16,000 students voluntarily chose to continue to be bused until the end of the school year.

There were no signs of confusion at Pacoima Junior High School in the eastern San Fernando Valley. Located in a poor, largely Hispanic neighborhood, Pacoima lost 57 white pupils -- about 70 percent of its Anglo students -- who until today had been bused there from their homes in the affluent western part of the valley, according to principal William Zazueta.

At the same time 240 children, about 75 percent of the Pacoima-area students who had been bused to the western part of the valley, opted to return. Zazueta said that he personally was happy to see mandatory busing come to an end.

"I doubt whether these decisions were being made in the best interest of the youngsters," he said. "I think the busing program was primarily the movement of minority youngsters, to their detriment. Society must look for methods to improve integration. But I wish society would stop using the public schools to solve its problems."

Trina Gracia, a 12-year-old seventh-grader at Pacomia who had not been in the busing program, said that the only difference she noticed on campus today was two homeroom classes rather than one. Julio Valazquez, a 13-year-old eighth-grader who had until today been bused to the western valley area, said that he was "just happy to be near home again."

Systemwide, about 50 additional teachers have been hired to handle the extra classes for the returning pupils. About 90 bus drivers have been given layoff notices. Thousands of school records and books have been shifted back to the neighborhood schools.

"I've very pleased we're off the roller coaster of mandatory busing," school board president Roberta Weintraub said. Weintraub's school board, with a strong anti-busing majority, voted March 16 to dismantle the busing scheme to achieve racial balance which had been in effect since 1978.

The school board's action was unprecedented. At least 23 percent of Los Angeles school district pupils are non-Hispanic whites, and the only city school districts in the past to dismantle busing orders have been those in which white pupils had almost completely abandoned the public schools.

The Los Angeles busing system had been ordered by Superior Court Judge Paul Egly on the basis of state law and state court decisions. California residents recently voted by 2 to 1 to eliminate these legal props for the Los Angeles busing scheme, and forced pro-busing groups to first prove intentional segregation busing could be ordered.

Egly's plan had forced more than 23,000 of the district's 529,000 pupils to take buses to distant schools. The school board said in March that it would allow the parents of any of the 23,000 pupils to sent their children to neighborhood schools today, the first day after spring vacation, and rejected pleas from teacher groups that the midterm shift would cause confusion and chaos.

Lawyers and school officials briefly were thrown into turmoil late Friday, when a U.S. district court judge unexpectedly issued a temporary restraining order to stop the return of children to their neighborhood schools. The judge agreed with lawyers for the National Association for the Advancement of Colored People that they still had a chance of proving that the school district was unconstitutionally segregated and that stopping the busing would cause irreparable harm to minority pupils in inner-city areas. On Saturday, a hastily convened three-judge panel of the U.S. Court of Appeals for the 9th Circuit overturned the restraining order, and Sunday U.S. Supreme Court Justice William H. Rehnquist refused an NAACP request to keep the busing system in place today. Rehnquist said, however, that he at least would hear both sides. But today the NAACP made this unnecessary when it withdrew its request for further hearings.