With more than 75 percent of mothers with school-age children in the county working outside the home, Prince George's school officials thought they were right on track last spring when they announced plans for a "Before and After School Care" program at elementary schools throughout the county.

Notices went home with youngsters, but when the tally was taken in May few schools had a commitment for the 60 pupils that officials said were needed to signal a go-ahead.

School officials, still sure of the need, opted to allow 15 schools to continue to try to register more pupils for the program. But by last week, six of the schools had signed up fewer than 30 children and the other nine had more but had not yet reached 60.

Last week, after a heated discussion between parents and educators at the school board meeting, school officials granted an extension allowing the nine schools with more than 30 pupils enrolled in the program time to attract more pupils or outline a plan showing that the centers would be self-supporting with fewer pupils.

School board officials said they were willing to go ahead in the hope of building a benchmark from which the program could grow. "If we pulled it out now," explained board member Catherine Burch, "it would never be successful."

The centers were proposed to allow pupils to come to school facilities as early as 7 a.m. and remain there as late as 6 p.m. During the period they were not in class, the pupils would receive help with their homework and could participate in arts and crafts, music and free play.

The pupils would be supervised by special aides hired by the county. Parents would be charged $35 a week for the program.

School officials, under strict fiscal restraints, had initially said that 60 to 75 youngsters were needed to make the program at each school self-supporting. But Superintendent John A. Murphy said last week that parents have the option of paying higher fees to ensure that programs with fewer pupils would continue.

Many parents have complained that they did not receive the initial notices sent home with their children in March. Others said that some notices, saying that some programs would operate on a trial basis, actually discouraged parents looking for long-term day care from signing up.

Another stumbling block was the timing of the school board's choice of 15 schools. Since that vote was not taken until late May, some parents and educators said planning was difficult.

"We just didn't have the luxury of time in getting this started," board member Doris Eugene told the parents last week.

Despite the parents' concerns raised in that meeting, some board members noted that the school system's responsibility to children does not include day care.

"The school system is not in the baby-sitting business," board member Marcy Canavan said. "We do not owe it to the parents, and the taxpayers do not owe it to the parents."

On a motion by board member Paul Shelby, the board voted to extend the programs at the nine schools until Oct. 30.

"If they're unable to come up with a self-supporting plan, the programs will have to go," explained Monica Weaver, who is coordinating the program.

As far as next year, Weaver said, many of the wrinkles in the new program should be ironed out. "I would be surprised if it were not followed through next year," she said. "There's such a need."

The nine elementary schools going ahead with the program are Calverton, Carole Highlands, Hillcrest Heights, Hyattsville, Kenilworth, Marlton, Potomac Landing, Ridgecrest and University Park.