THE DISTRICT'S Youth Services Administration, which detains about 6,000 troubled adolescents each year, is supposed to be trying to show them ways to achieve a better life. But the YSA has performed so poorly that lawyers, suing on behalf of the young people, forced it into a court agreement that called for specific improvements. Two of the most glaring deficiencies involved poor schooling for the youths and staffing problems that supposedly required massive amounts of overtime. A court-appointed monitor, called in to check on compliance with the agreement, has now shed new light on both of these concerns.

A 1982 manpower study of the city's juvenile detention facilities found that a typical staff member annually averaged 13 days of sick leave, 15 days of paid absences for "injuries," seven days of absence without leave and 30 days of leave without pay. None of that included the 23 days of annual holiday and regular leave a staffer was already entitled to. That meant the average staffer was unavailable for work for one-third of the year. The monitor says the current situation "does not differ markedly." The average YSA staff group leader has been averaging 45 days of absences from work per year, again not counting holiday and vacation leave. What kind of example is this? Even the school secretary was out for nine weeks of "stress leave."

All this bears on YSA's mandate to provide education to its charges at least five hours a day. Of 36 possible school days at the city's Oak Hill facility in March and April (not counting spring vacation), the school was closed 15 days. This is an appalling performance for youths who already question the importance of an education. None of the required records have been kept. Only five of the youths who need special education have individual lesson plans, and no one has a list that shows how many more students need special education.

Jesse Williams Jr., the city's new youth services director, recently said that 269 new employees will be sought to address the staffing problems. Mr. Williams may need to hire even more. That's because some of the people on the payroll now should obviously be fired . . . and soon.