Prince William County's first school-age child-care program is in danger of failing because not enough participants have signed up.

Officials have extended the application deadline until Aug. 3 because fewer than half the required number of children have signed up for the pilot before- and after-school care program in seven schools.

The county mailed applications to parents of all 4,000 elementary school children eligible for the program, but received only 176 completed forms by the July 20 deadline, said spokeswoman Susan Mack.

"We're amazed by the reduction in the level of response," said Acting County Executive Connie Bawcum.

To break even, the county needs at least 27 children at each of the elementary schools: Marumsco Hills, Neabsco, Nokesville, Occoquan, John F. Pattie, Springwoods and West Gate.

All schools have vacancies, and Nokesville has only four children signed up for the afternoon session, which runs from after school until 6:30 p.m., and six for the morning session, which begins at 6:30 a.m.

If the county does not receive enough new applications, the supervisors will have to decide on Aug. 7 whether to cancel the program or subsidize it, said Deputy County Attorney Lawrence Hughes. The county and the day-care provider hired to run the program, Minnieland Private Day Schools, have already invested $61,000.

The program, which will cost parents $25 a week for the morning session, $29 for the afternoon or $48 for both, is open only to children who attend the seven schools.

Fairfax County has run a similar program since 1975. Currently 5,000 children receive child care at 101 centers, and the program's waiting list averages 400 to 600, said Patricia McClenic, spokeswoman for the Fairfax Office for Children.

Parents interested in Prince William's program can call program coordinator Karen Severn at 335-6091.