The Loudoun County School Board has mobilized the largest community effort in its history to ensure passage of a $50.3 million bond issue that would be used to build and equip five new schools by 1991.

Led by outgoing School Board Chairman Warren Braham and four former school board chairmen, the Loudoun Citizens for Quality Education committee has mobilized several dozen county residents and administrators into five subcommittees whose duties will include encouraging voter registration for the Nov. 4 ballot, operating a speakers' bureau and raising money for informational brochures and fliers.

County officials said the projected growth in the eastern Loudoun and Leesburg area -- where the three elementary schools, a middle school and a high school will be located -- is 1,059 housing units per year. Projected elementary school enrollments for the area have nearly doubled since 1984, from 774 to 1,414, they said.

More than 4,000 students, most of them at the elementary level and most in fast-growing eastern Loudoun, are expected to swell school rolls in the next five years. These figures do not take into account the newly approved Ashburn Village development, which will include 5,000 homes, or the Dulles North Plan, a 34-square-mile area east of Dulles International Airport. The housing density there will range from 1.6 housing units per acre to 4.0 units per acre in some areas.

"We always want a seat ready when the child arrives," said School Superintendent Robert Butt. "We were caught short once in the early 1970s when masses of people moved into Loudoun and we had to go to year-round schools and busing to play catch-up. We've tried to avoid that kind of disruption every since, by being prepared."

According to Butt, who has served as superintendent since 1969, Loudoun schools have historically been financed through successful school bond referendums, the last one in 1978 when a $10 million bond issue paid for two elementary schools, one in Leesburg and one in Loudoun's eastern end. School officials expect little or no resistance to the fall bond referendum, Butt said.

Linda Reinhardt, an eastern Loudoun resident whose two sons graduated from county schools, is cochairman of the special events committee that will distribute literature during parades and festivals in the county. The first event at which the committee will have a booth is August Court Days, Aug. 16-17, the annual two-day festival at which an 18th century court opening is reenacted, accompanied by crafts, exhibits and dancing in the streets of Leesburg.

Committee members also expect to be on hand during a Columbus Day parade in Sterling on Oct. 11, the Bluemont Fair on Sept. 13-14 and a trade fair at the C.S. Monroe Vo-Tech Center in Leesburg on Sept. 27-28. "A bond referendum is the best and cheapest way for the taxpayers to pay for the schools this county needs," Reinhardt said. "I worked for the last bond referendum, too."

The speakers' bureau committee, in cooperation with the civic association liaison committee, has already begun setting up speaking dates for the fall meetings of county groups. The finance committee has raised $2,000 toward its goal of $10,000 to pay for fliers and brochures. The state code prohibits the use of school funds to finance such efforts, school information officer Molly Converse said.

"We feel once the community understands the numbers enrollment projections they'll also understand that maintaining quality schools is one of the ways we can control the quality of growth in Loudoun. You attract the right kind of industry if you have good schools," Converse said.

If voters approve the bond issue, Butt said, design plans will begin "the next day." Construction of the first two elementary schools could begin next spring.