Two window air conditioners are roaring, but 100-degree heat stifles the cafeteria. For years, the students and staff at Round Hill Elementary School have sweltered in the multipurpose room.

But not after this month.

The Loudoun County public school is closing because it is too small and too old to accommodate growing numbers of elementary-age children filling its classrooms. A new school nearly three times its size, also called Round Hill, will open in August about a mile away.

It will be the first new school built in the western reaches of the county in nearly 30 years.

At 88, Round Hill is tied with Middleburg Elementary as Loudoun's oldest school. Both campuses opened in 1911 and have been through several additions and renovations in the last eight decades.

Molly Converse, a spokeswoman for the 26,000-student district, said school officials are considering what to do with the old Round Hill. The building might be used for storage, as a regional center for cafeteria supplies and other shared services, or as a teacher training center.

"Growing as we are, we have lots of proposals," Converse said.

On Sunday, generations of graduates, teachers and other members of the Round Hill community attended a party at the western Loudoun school to honor its long life and mark its demise. About 300 people attended, sharing photographs, report cards and other memorabilia from the school's history.

The school is one of nine in western Loudoun that enrolls fewer than 300 students and has age-related shortcomings. Many of those schools have remained open for so many years because the residential development that is consuming eastern Loudoun has been slower to arrive in the west.

But with home-building heading west, school officials considered expanding Round Hill. That was economically unworkable. In 1997, voters approved a new, $9.8 million school that will have a capacity of 650 students.

The staff at Round Hill said it intends to maintain the school's intimate atmosphere even though enrollment will nearly double next year.

"I think this community is one that is tight-knit enough that they're going to bring the feeling of a small school into a big school," said Alma Brown, a fourth-grade teacher who has worked at Round Hill for nine years.

The original school, a two-story stone structure that cost $392.18 to build, initially enrolled students in elementary and high school. The first seniors graduated in 1914 and the last in 1941. By 1971, Round Hill enrolled students only in kindergarten through fifth grade.

Two additions were built, in 1963 and 1968. In the '60s, most of the old stone building was demolished.

The pressures of residential development have been increasing on Round Hill Elementary. Enrollment neared the school's capacity of 300, and this year it was capped at 262. New students in the boundary area were sent to Hillsboro and Emerick Elementary schools, according to Principal Mary S. Brecht. Those students and any new ones will attend the new Round Hill in the fall.

School staff members have gobbled up every corner of building space. One classroom used for art and music classes also acts as storage for physical education supplies. Next to the main office, a makeshift teacher's lounge with a photocopying machine, refrigerator and coffee pot doubles as an exam room for the health aide.

But cramped quarters also foster a feeling of closeness. It is an atmosphere the school community is determined to retain, no matter how much it grows.

"It'll be more challenging, but it's not impossible," Brecht said. "A sense of family comes from people, not a building."

CAPTION: Dressed in his finest '60s-style threads, Eric Rothschild, 9, commemorates closing of Round Hill Elementary at gathering Sunday.

CAPTION: Round Hill students put on a parade Sunday depicting eight decades of the school, which at 88 ties Middleburg Elementary as Loudoun's oldest. A bigger school will open about a mile away in August.