Fairfax Christian Academy often crowds 35 or more students into a classroom, has no school teams or extracurricular activities, requires kids to bring their own lunches, seldom has a parents' meeting and charges tuition of $1,350 a year.

But families are lining up to get their children in.

Its clientele includes such prominent parents as Sen. Strom Thurmond (R-S.C.); Richard A. Viguerie, master fund-raiser of the New Right; Howard E. Phillips, founder of the Conservative Caucus; Rep. Philip M. Crane (R-Ill.), former presidential candidate, and New Right political organizer Morton Blackwell.

Robert L. Thoburn, founder, director and headmaster of Fairfax Christian, only chuckles at the suggestion that his profit-making school is an exclusive haven for the newly influential conservative political elite -- a sort of St. Albans School for the New Right.

Former liberal Democratic senator Birch Bayh sent a child to the school briefly in the 1960s, Thoburn notes, and children of Redskin quarterback Joe Theisman attended more recently.

But Thoburn is the first to agree that Fairfax Christian, by virtue of its prestigious clientele, is giving a mantle of establishment respectability to an educational "movement" that Thoburn believes could revolutionize American education.

His is one of a growing number of Christian schools that stresses fundamental religious values and teaches courses ranging from the story of man's evolution to economics from a "Christian perspective." $ the critics of this development warn that its success has been built on parental fears of forced busing and concern over deteriorating public school discipline and the ban on school prayer. They also contend that many of the fundamentalist religious leaders who promote Christian schools have a political agenda that includes wider mobilization of religion for the causes and candidates of the New Right.

Thoburn himself, in addition to three unsuccessful runs for Congress, has served one term in the Virginia House of Delegates. One of his sons is legislative affairs director of the Moral Majority and another works for the Life Amendment Political Action Committee, which is raising money for the campaign to ban abortion.

Yet for all that, Thoburn insists that it is mainly the no-frills academic program, rather than religion or politics, that has pushed enrollment in kindergarten through grade 12 to around 500 students this year and helped him achieve a net worth of more than $1 million since he started his first school in Arlington in 1961.

That Fairfax Christian, just south of the city of Fairfax, is serious about practicing traditional education is evident from the old-fashioned "little red schoolhouse" mood that pervades its classrooms.

First-graders get some of their initial exposure to school texts in the pages of McGuffey's Reader, the standard 19th Century textbook whose pages are adorned with illustrations of little boys in sailor suits, mothers with ample skirts and parasols and grandfathers with mustaches and three-piece suits.

Kindergarten children, put through their paces for a visitor, recited scripture, sang and took turns reading aloud from a book. In this class, children were learning reading through phonics -- identifying and pronouncing sounds -- rather than through the technique of "look-say" which became fashionable in the 1960s.

At the teacher's request a 5-year-old went to the blackboard and underlined the "o" and "u" in the word "sound," correctly identifying the vowels that sounded the same as in "house."

Next door, a teacher using a multiplication wheel led the class in a recitation of the multiplication tables. Each time a new series of numbers came up, they were recited by sub-groups -- girls, then boys, then children in the front row, and so on.

Tests, homework and order clearly play an impartant part in the kind of education that children are getting at Fairfax Christian.

Parents whose children are late turning in homework get a call from the school secretary suggesting that they with the problem.

The no-nonsense approach extends, as well, to discipline. Talking during tests means an automatic zero and students who damage property or misbehave have to pay for it or work for the school.

"We feel children should take responsibility for their actions at a younger age. We rarely use physical punishment -- and only with younger children. But we do feel they should make restitution in some way," says Thoburn.

Thoburn, a Presbyterian, founded his first Christian private school in Arlington in the fall of 1961, with the help of his wife, Eleanor, whom he met while studying at Muskingum College in Ohio. Since then, he says, 15 similar schools have opened in Northern Virginia.

Although considerable national publicity has recently been focused on the attempts by religious groups to force public schools to teach the biblical interpretation of creation along with scientific theories of evolution, Thoburn says that the religious school movement wants to go much further to develop a whole Christian curriculum "that would even get down to the Christian philosophy behind mathematics, the sign of an orderly universe."

Thoburn himself teaches economics and utilizes Gary North's "An Introduction to Christian Economics."

The Bible, says Thoburn, is filled with practical economic guidance. There are strictures in Isaiah, chapter one, against mixing silver with dross, an admonition against diluting the value of the currency, as happened "with Lyndon Johnson's funny money." Thoburn adds that Old Testament passages establish guidelines for responsible management of bank reserves.

Yet for all of Thoburn's dreams of a "Christian curriculum" set apart from that of the public schools, much of the teaching at Fairfax Christian seems anything but radical.

At the Bible class given by Robert Gifford, who doubles as the after-school physical education director, students conscientiously jot down notes about the Resurrection as the "hope of the Christians," and listen to several pointed warnings about the "indoctrination" of young people by contemporary cults.

But history teacher Dan Heinze's treatment of the homestead movement in the last century sounds like any high school lecture.

"In talking about the ideas that led the American people to the point of revolution we do look at the feelings of Christians against tyranny that went back to the 16th Century . . . but this is a history class, not a Bible class," says Heinze, a graduate of Bob Jones University.

"You can't always have religion in everything," echoed one student. "Some things are just facts."

Thoburn takes the view that the results of Fairfax Christian speak for themselves. Most graduates go on to college, the school has produced several students who were near the top of the state on national tests, and the cost per pupil is, he says, about half that of the Alexandria public school system.

Thoburn and his wife are vague about the numbers of black children attending the school, saying "we don't keep track of that." A recent graduate was the daughter of Jay Parker, a black who heads the conservative Lincoln Institute in Washington.

And Thoburn says with a chuckle that his only racial problems are with white parents who insist that their children be placed in the same classroom as blacks.

Supporters of the school say that its traditional, no-frills style could become the way of the future if public schools have to keep cutting back their budgets.

The director says that class size is not a problem in his school because students are well-behaved. "When people say they want small classes it is usually a tipoff there are problems with the kids," he says.

But critics of this kind of private school say their objections go beyond the concept of Christian curriculums. They say such schools are successful only because they can pick and choose whom they take, and because they operate a stripped-down program that leaves it to others in the community to provide sports and extracurricular activities.

And they ask whether the "back-to-basics" program that parents increasingly want adequately challenges young people to take responsibility for their own education rather than relying on rigorous teachers to tell them what to learn.

For his part, Thoburn does not agonize over these difficult questions, preferring to let his own success speak for itself.

"We have made a very good profit running a private school," he says. "I'm not ashamed of it."