Three weeks ago it looked as though Prince George's County's highly promising experiment in school desegregation was in danger of collapsing. The state had reportedly decided not to provide more than a fraction of the $13 million that it will cost to carry the new magnet schools into a second year. Then last week the advisory Committee of 100 reported to the county's school board that the requirement actually was not $13 million next year but more than $40 million. In addition to the magnet schools, it said, the county needs more teachers at higher salaries for the children who are not in the special magnet programs. There was talk of new taxes, and the prospect of another futile collision over money in the General Assembly.

Instead, County Executive Parris Glendening has now stepped forward to announce that the county will put up the $40 million from its own funds. As Mr. Glendening said, it will be the largest single increase for education in the county's history. It couldn't have come at a better moment.

Prince George's is now managing school policy with a kind of political skill and energy that commands real respect. The change in recent years has been dramatic. One ingredient is Mr. Glendening. Another is the school superintendent, John Murphy, who has wagered his own job on his ability to raise the academic performance of the county's children. In turn, he has imposed performance standards on the county's school principals and teachers. That gives the politicians like Mr. Glendening some assurance that, in spending more money, they will get something of value to show for it.

A third ingredient is the Committee of 100, which is turning into much more than the conventional citizens' cheerleading squad. School policy in Prince George's has revolved for 14 years around the desegregation suit brought by the NAACP and fought out in federal court. Under the chairmanship of John B. Slaughter, the chancellor of the University of Maryland, the Committee of 100 has now undertaken the responsibility for monitoring the court's desegregation plan. The NAACP is represented on the committee, and issues that might have been carried into court are now being discussed and reconciled within this vigorous organization.

The committee's report last week to the school board emphasized the consensus that the school system is now working in good faith to carry out the desegregation plan. That provides assurance to the county's taxpayers that increased funds for the schools will go into education and not into adversary jousting and litigation. As the Committee of 100 said, "the community seems to have adopted a renewed sense of commitment to the county's educational system and its children."