Fairfax County school officials plan to replace the world history and geography classes taken by most ninth-graders with a new course emphasizing Asian, African and other non-Western cultures.

The new class, to be organized around themes, such as religion and revolution, instead of chronology, has sparked wide debate among county history teachers. Skeptics say the new course is no substitute for an important basic subject; its proponents claim it will enhance students' thinking skills and broaden their outlook on the world.

The growing debate in the area's largest school system mirrors similar disputes at secondary schools and universities across the country in recent years.

In New York State, for instance, a task force last year recommended a new multicultural history curriculum to provide minority students "higher self-esteem and self-respect" and reduce the "arrogant perspective" of white students. Last year, after a two-year battle, Stanford University replaced a required Western cultures course with a new one weighted more toward the study and writings of women and minorities.

Fairfax County School Superintendent Robert R. Spillane, concerned that current classes do not include enough non-Western material, has authorized two teacher committees to design the course and choose textbooks.

The result would be tested in a pilot program involving hundreds of students next year and, if approved by Spillane and the School Board, expanded for all 10,000 ninth-graders in 23 high schools the following year.

"The culture of people in the Middle East, the culture of Japan -- we need to know all that," said Frank Taylor, the system's social studies coordinator, who is helping to plan the course. "It may be that 100 years ago we didn't need to know all that, but it's a smaller world now."

"To us, it just doesn't make sense to destroy the integrity of a discipline to achieve a nebulous goal," said Roe Buchanan, chairman of the social studies department at Centreville High School.

Elsewhere in the Washington area, the debate has taken different shapes. Parents and educators in the District and Prince George's County, where there are large numbers of black students, are discussing how to put more emphasis on African culture in social studies courses. Montgomery County school officials over the last three years have been injecting their U.S. history courses with more lessons about women and minorities.

In Fairfax, about half of the ninth-graders now take history, while about 40 percent take world geography. The remainder choose a course called world cultures.

Under the plan, all three would be eliminated in favor of a single, integrated course, and world history would be introduced in the 10th grade, but as an elective.

In the new ninth-grade course, all students would study themes such as major religions or revolutions. For instance, Taylor suggested, a lesson might look at how individuals can affect the world, focusing on such major historical figures as Hannibal, Julius Caesar, Joan of Arc, Winston Churchill and Nelson Mandela.

Such an approach encourages critical thinking, instead of mindless memorization of dates and places, advocates maintain. "As important as it is to learn about the Civil War, it's more important to understand why people fight and what the effects of war are," Taylor said.

Although this method was widely used in the late 1960s, it faded in popularity. Then last November, the National Commission for the Study of Social Studies in the School, a panel created by several education think tanks, touted the approach in a special report.

"It's the national thing now," said Fairfax Deputy Superintendent Loretta C. Webb.

While curriculum changes normally do not need School Board approval, officials said they will seek it in this case because the overhaul is so significant. The board will be briefed on the new curriculum in March.

A few schools in Fairfax already have independently merged history, geography and cultures into a single course, and teachers said the reception has been positive.

"We do have to make our students sensitive to the rest of the world," said Linda Driscoll, social studies department chairwoman at Falls Church High School, which introduced such a class this fall. "That's simply reflecting the diversity that's going to happen in this county by the year 2000."

"The bottom line," said Kurt Waters, who teaches world history at Annandale High, "is we want to teach kids there are things worthy of study in all cultures . . . that America can no longer sit on a pedestal and say, 'Let everybody come to us and understand our culture.' It's a two-way street now."

Some teachers have written strong letters of dissent to school officials. Until students have a grounding in world history, they cannot hope to compare events in different eras, they said. Moreover, some teachers have said, playing down the importance of Europe would be ignoring its influence in America.

"Europe provided this country with its political and philosophical underpinnings," said Dennis J. Pfennig, social studies department chairman at Hayfield Secondary School and a skeptic about the new course.

Pfennig said school officials are "jumping on the bandwagon of trendiness" by trying to "artificially mishmosh" a world studies class. "I predict we'll turn out an entire generation of ignoramuses," he said.