In fast-growing districts such as Prince William County, new schools get most of the attention from the public -- one new school opened last year, five new schools are coming this September, two new schools are scheduled to open in 2005.

But overlooked in the buzz over the new schools is the work required to keep the older schools running. For all the schools the county has built to keep up with burgeoning growth, more than 60 percent of its facilities are more than 21 years old.

So every summer, when the last teacher packs up the last box on the last day of school, workers move in, ready to start the season's major maintenance.

This is one of the busiest times of the year, said Dee Thompson, a project manager for Prince William schools. At Sudley Elementary, a 32-year-old school getting special attention this summer, "we literally had people in there immediately after school let out," Thompson said.

Sudley, built in 1972 when open-space classrooms were a popular educational trend, is getting cinder block walls like newer schools. Instead of classrooms separated by thin partitions, each teacher will have a room with a door. This is the second of two summers devoted to the $4.5 million project. In addition, the Manassas school is getting a new parking lot.

Thompson said his crew worked all weekend after the last day of school, June 18, moving furniture and equipment out of the way. The contractors rolled in June 21. And they're moving fast, said Principal Pam Moody. "They've already started painting," she marveled. "We cleared out, and they barreled in."

That's the way it works at many of the schools getting major renovations, Thompson said. His day starts at 6:30 or 7 a.m., at one school or another. He checks in with the big projects such as Sudley at least once a day. In addition, he's overseeing new schools under construction.

He also tries to make it to his office two or three times a week to deal with paperwork, though much of that will wait until fall after school reopens.

The county tries to devote about 3 percent of the replacement cost of all schools to renovations, repairs and maintenance. For the next fiscal year, that will be about $25 million, according to the school system's capital improvements program.

Renovating older schools can be tricky, Thompson said. Building a new school means following the blueprints. But for older schools, accommodations have to be made for the personality of each facility.

For instance, at Sudley, the lack of barriers between classrooms made it easy for teachers to gather students from different classes for computer work. Because they want to continue to work with large groups, the walled classrooms include more outlets for computers than would the typical new classroom.

"Sometimes you have to be sensitive," Thompson said. "These are concerns that you don't have at a new school."

The pace of reconstruction may be hectic now, but as fall approaches, "it gets into a whole other gear," Thompson said. At times, the fire marshal has conducted alarm inspections at 2 a.m. to accommodate the school system.

Meanwhile, school employees have to clean up and move furniture back into place.

Having been through this for one summer already, Moody said she can't wait for Sudley's teachers and students to see the finished product.

"It's like a brand-new school," she said.