The Montgomery County Planning Board has deferred a proposed residential subdivision for the second time this month, because staff reports indicate that county schools in the area are overflowing and cannot accommodate more students.

The board deferred a decision until May on what is known as the Kay II Property, a 159-unit subdivision planned for Aspen Hill. In May, the County Council and the school board are expected to hammer out a capital improvements budget that will dictate how many new schools are to be built and where, said Charles R. Loehr of the county planning staff.

Because the County Council is concerned about the cost of new schools, it has asked the planning board to consider school capacity when considering new subdivisions and, if necessary, to invoke a state law that allows localities to deny new housing if there are not enough public facilities to support the new residents who would move there.

According to staff reports from the county school system, the Kay II subdivision and a 144-unit subdivision near Burtonsville that had been considered the previous week would generate more students than the county could accommodate in existing schools. The planning board's own staff recommended that plans for both subdivisions be denied on these grounds.

But the board voted instead to defer decisions on both subdivisions until after the capital improvements budget is finalized and a new school plan is in place.

"The courts take a dim view of school capacity being the sole reason for denial," board member Mable M. Granke said after the vote to defer the first subdivision earlier this month.

The planning board makes recommendations on planning requests to the County Council, which makes final decisions.

Like other Maryland communities, Montgomery County has faced an increase in student enrollments at the same time that the state has cut back on aid for school construction. Concerned about the tremendous amount of money the county will need to borrow to build new schools, County Executive Charles W. Gilchrist has recommended that the county scale down slightly the six-year, $248 million school-building program proposed by the school board.

Meanwhile, developers have started to complain that the county is using the Public Facilities Ordinance to shirk its responsibility to build sewers, roads and schools to accommodate its new residents.

"This is an issue that is being hotly debated in front of the board," said John Hoover, planning board spokesman. "I imagine it will become more frequent if the schools issue is not resolved."

The board's staff last week also urged the board to recommend denial of a proposed 24-unit subdivision in Fairland-Beltsville because neighborhood schools are filled to capacity, but the board recommended approval of the project because of its small size, Loehr said.