Next fall, the students at George Mason Junior-Senior High School in Falls Church, home of the Washington area's smallest public school system, will choose from course offerings including gourment foods, data processing, calligraphy and advertising persuasion.

'Small is beautiful" describes the prevailing atmosphere at George Mason, where the school offers 112 courses to fewer than 650 students and teaches any that draw 10 or more students. Smallness also means that more than half of the students participate in sports, on opportunity confined to the most talented in larger schools.

But this variety and richness designed to "educate the whole child" in current educational parlance, is expensive, Falls Church's per pupil costs are among the highest in the state and pose a threat to the school systems future.

"They can't continue with that many courses, said Jackie Droujinsky, 38, mother of two students and a veteran of high school curriculum committees. "They aren't all quality courses. We'll have to make prorities."

Mayor Harold Miller demurred: "As long as there is not substantially any reduction in the school-age population, we can go on" operating what he describes as an "economically viable school system.'

Cost and quality are two issues currently being debated in aging suburban communities across the country like Falls Church, a 2-square-mile city of modest homes with large shade trees and neat lawns squeeze between Arlington and Fairfax counties.

Today in Falls Church, population: 9,259, only 20 percent of the families

SHIRNKING, from c1 have school-age children. This is partly the result of declining birth rates and the area-wide rise in property values which put single-family homes out of the reach of many young parents. In 1975 Falls Church lost 470 units of low income housing which were replaced by condominiums and $90,000 three-bedroom townhouses.

"The impact of the loss of the body boom has already worked its way into the schools," said Falls Church School Superintendent Warren J. Pace. "We are down from a high enrollment in 1965 of 2,350 to 1,159," a los of nearly 50 percent.

As enrollments decline, the cost of maintaining all the services needed for a quality system rises proportionally.

Virginia accreditation standards call for "an adequate staff" of nurses, speech and hearing therapists, psychologists and other specialistes. Accounting standards require further personnel, and schools need maintences and clerical help. These services necessarily serve fewer people in a small system than they might serve in a large one.

Consequently, Falls Church's perpupil operating cost (including teacher salaries) next year will be $3,500.

"With the exception of Airlington, that's probably $1,000 ahead of everyone else," said superintendent's assistant Doug Scott. He noted that in 1977-78 the schools requested $3.1 million from the city Council, a per pupil cost of $2,276. The request stayed the same in 1978-79 but the per pupil cost rose by 8 percent to $3,100 due to the decline in enrollment.

School officials interviewed recently maintained that the quality of education offered in Falls Church will continue to justify the high cost to the community. "Some say we'd rather have potholes in our streets than gaps in our children's educations," said Superintendent Pace.

In support of George Mason's size and quality, Associate Principal Nancy F. Sprague said, "it's impossible for a kid to get lost here. We know everytinng about them . . . their test scores, their home life, who their boyfrends and girlfriends are. We set up systems where everyone's needs are met."

But there are some parents who feel the system is too emall and their needs aren't being met.

Donna Owens, 39, taught sixth grade in Falls Church for nine years. Describing herself as "burned out" from a "terribly draining job," she has taken a leave of absence from school for the fall.

"Something is lost in tailoring the curriculum to fit the kid," she said. "Standards are lowered."

Owen disagrees with the present grading system. "The theory has been individualization," the teacher said. "You compare a child to his own potential, not to anyone else. That's an unrealistic attitude. That's not what the world demands.School has become a nice happy place where one does not fail because it messes up their psyches."

Jackie Droujinsky is sending her son to a private school next fall. "He's not a disciplined kid," she said, adding that school officials "agreed he needs more stucture."

In response to similar complaints, School Board Chairman Elizabeth Blystone said, "We've had a little stricter discipline in the last few years . . . we've also strengthened requirements for graduation. Kids were leaving without basic skills."

According to H.P. (Ducke) Strople. 77, a former school board member and Falls Church resident since 1945, the city was founded in part because of the citizen's desire to have better control over how their tax money for schools was spent and also to ensure schools within walking distance for their youngest children.

Next fall, kindergarten and first grade will meet in one elementary school building, grades 2-5 in a second, and the remaining biilding will be used for city offices. The majority of children will be bused.

"If we're goint to transport the children," said Strople, "why not get Fairfax County to do it for $1,700 less?" Strople feels it would be "better for the children if they were under the supervision of a larger, better system" like Fairfax County's.

School Board Chairman Blystone points to the record of the City Council's continued support of the Falls Church school budgets and dismisses the idea of rejoining Fairfax or any other county school system. Besides, she said, "Fairfax and Arlington don't want us.

Arlington County School Board Chairman Ann Broder disagrees. Noting that the board has not discussed the subject to tataking over the Falls Church schools, she said, "It would take a reasonable amount of negotiations, but speaking for myself, I think we would be delighted to have them. We have a physical plant that needs to be filled with children."

Fairfax County School but said, ". . . were there to be acceptable contract terms we would entertain having an arrangement whereby (Fairfax) County would run [the Falls Church] schools."

The Falls Church Shool Board and school administrators are aware of the shaky foundation on which their system rsts. To counter potential shockes in the future, they have taken a number of steps.

This summer all programs are being reviewed for potential cuts. Already the schools offer adult education and extended day-care. Parents and students serve on committees restricted in large areas to school personnel. Other committees have been formed to find solutions for morale problems among the teachers who constantly face the specter of staff cutbacks and have no room for lateral movement. CAPTION: Picture, HAROLD MILLER . . . "we can go on"