Gladys and Leonard Dement built their house in the evenings when he got home from work, on land that had been in the family since she was a baby.

But when state officials decided years ago that ponds were needed in the Indian Bridge Road area of St. Mary's County to prevent flooding in Great Mills, the Dements had to sell their 72 acres, after a long fight, and move away.

She lives a few miles from their old farm, but in more than 30 years she has never gone back. "I didn't want to see what they had done to my home," she said.

When she heard that the land might be redeveloped, she got mad all over again. She's just one of the neighbors around Indian Bridge Road who are angry about talk of building schools there and worried about the possible expansion of the nearby Lexington Park development district, which could bring rapid growth to their rural area.

"Where would it stop, once you started?" said Linda Vallandingham, who collected hundreds of signatures on a petition she submitted to the St. Mary's County commissioners.

But St. Mary's public schools officials say finding land for schools -- fast -- is critical.

On Tuesday, outgoing Superintendent Patricia M. Richardson, along with acting Superintendent Lorraine Fulton and other school administrators, showed the county commissioners maps with red dots pinpointing possible land for schools.

They're working against a late-January deadline set by the state. If they miss that, they will have to wait another year for approval of a site. And with a handful of new elementary schools needed over the next several years, and middle and high schools down the line, the St. Mary's officials want to get started to make sure classrooms don't become overcrowded.

"We know site selection is often controversial," Richardson said. It could mean redistricting, busing, more traffic, environmental issues. Where districts have chosen land successfully, she said, "the one magic wand" that made it work was that their elected officials "were always able to stand together."

They told commissioners that land on the east side of Indian Bridge Road, where they would like to build an elementary school, has cleared one hurdle but that they are not sure it will be ready by the deadline.

On the other side of the road, in the woodlands that have been at the center of a controversy involving the state and a politically connected Baltimore businessman, St. Mary's school officials are still hoping for 150 to 200 acres for a complex of schools. Willard Hackerman, owner of the Whiting-Turner Construction Co., who had talked with the state about buying 836 acres that encompass the potential school sites, recently dropped that proposed deal but said he would be willing to donate $1 million to St. Mary's County.

Some of the area around Indian Bridge Road is not zoned for development because of concerns about the St. Mary's River watershed. But that could change with a proposal to expand the boundaries of the Lexington Park development district, which has prompted objections from neighbors and environmentalists.

"That land was set aside for protection," said Robert Paul, a biology professor at St. Mary's College of Maryland who has studied the St. Mary's River. "Development is running pretty rampant in the rest of the watershed, so we need to be pretty careful and not develop property set aside for protection."

Others say flooding concerns have been overblown. For example, commissioners President Thomas F. McKay (R-At Large) said strict regulations about construction will prevent problems.

A developer might donate land for an elementary school near Wildewood. That option also could lead to an expanded development district and more houses nearby, but it would leave the county with more money for buildings and classrooms because it would not have to buy the land.

The county owns land in Spring Ridge and Great Mills, but school officials said those sites are not ideal because students would have to be bused a long way from the elementary schools that are overcrowded.

School officials checked on 67 sites, said J. Bradley Clements of the St. Mary's County school system. About half of the landowners did not answer letters from the school system, he said, and a third or more said they were not interested in selling.

"We're not opposed to schools," said Vallandingham, the petition drive's leader. "We know there's a desperate need for schools. But not in this location.

"Not because it's our back yard, but for environmental reasons," she said. "Because that land was bought to protect the watershed and to prevent Great Mills from flooding. We don't want a precedent set."

Bill Sievers rides on the land where education officials want to build schools. Critics want the area preserved to protect the St. Mary's River watershed.