IN THE MATTER of racial desegregation, the Prince George's County schools have set an example that is in nearly every respect a model. During the current litigation, federal Judge Frank A. Kaufman has conducted a searching examination of the schools' performance. His opinion, handed down several days ago, is an extraordinary affirmation of the school system's vigor and good faith in its attack on racial discrimination. Where he found flaws in the record, they are rather minor. A reading of that long and detailed opinion will strengthen the confidence of Prince George's parents and voters in the spirit of fairness that over the past decade has guided the county's schools.

Judge Kaufman has decided to resume jurisdiction in this case, at least a little longer, on grounds that the job of desegregation is not yet complete and that his earlier order was, although innocently, violated in one instance. That conclusion is a matter of disappointment to the school board. But the judge also acknowledges the difficult circumstances under which the schools have been making progress.

The Prince George's schools remained highly segregated until very late in the day--1973, when Judge Kaufman's first order took effect. Since then, the schools have also been dealing with demographic change on a scale that knocked their carefully balanced assignment plans awry as soon as they were made. Black students, 31 percent of the school system's enrollment when the first order took hold, are now 54 percent. Meanwhile, the number of children in the school system has fallen by nearly a third since the peak, in 1972, and 64 schools have been closed, with all the usual disruption and distress.

In the background of this suit are, significantly, complaints from black parents that their children were being bused too far to schools that, with rapidly changing residential patterns, were becoming preponderantly black. Four years ago the then president of the county's NAACP began talking with the school board about reductions in busing. That led to a furious row within the NAACP, the plaintiff in the original desegregation case. Two years later it returned to the courtroom with the present suit, charging that the county schools were using a wide range of tactics--in hiring, in the assignments of students and teachers, in the special education programs and in the disciplinary procedures--in a deliberate campaign to perpetuate racial segregation.

Judge Kaufman carefully considered each of these accusations, and dismissed them all. In an unusual compliment, he said that over the past decade he has come to have "the highest regard for the sincerity and integrity" of the staff people who have been running the county's schools.

The judge added the hope that at "some date not too far distant" he will be able to declare the Prince George's system fully desegregated, or at least able to operate without any active supervision by the court. On the basis of a decade's hard and honest work, the school system is now very close to the point at which it is entitled to that status.