The no-smoking policy instituted for students at Arlington's four high schools last fall appears to be working, principals and other school officials said last week.

Until last fall, students aged 16 and over were allowed to smoke in designated outdoor areas on their school campuses if they had parental permission. The county School Board, pointing to the contrast of permitting smoking while students are lectured on the health risks of the practice, eliminated the smoking areas.

When the board approved the smoking ban last June, some school officials and students predicted that it would be unenforceable and would prompt students to seek out bathrooms and other indoor areas where illegal smoking was already a problem.

The principals and some students interviewed last week said some smoking persists, but the ban seems to be working for the most part.

Students caught smoking at Yorktown, Washington-Lee and Wakefield high schools are sent to a 90-minute after-school seminar during which films provided by the American Cancer Society are shown in conjunction with discussions about the dangers of smoking. About 300 students have attended the seminars since the fall.

"They're pretty gory films," said Yorktown biology teacher Clarence Seldomridge, who teaches the seminars three days a week. "I'm not going to say all the students have quit smoking, but it's worked well."

If students fail to attend the seminars or are caught smoking again, they can be assigned "in-school" suspensions, which require them to stay in one room all day. Further violations can lead to suspensions and parent-principal conferences.

"We want to make them understand we feel this is important enough" for such a conference, said Washington-Lee High School Principal William Sharbaugh, adding that students who repeatedly violate the ban will be told to "make a decision on whether they want to stay" in school.

Ray Anderson, principal at H-B Woodlawn Secondary School, which has about 400 students in grades seven through 12, said few of the students there smoke. Because the school is so small and the number caught smoking so few, Woodlawn has no seminar program; students caught smoking are given automatic one-day suspensions.

Dennis Hill, principal of Wakefield High, said most students have cooperated with the ban. But he added, "Students who are going to smoke are going to find places to do it."

Some students at Washington-Lee last week said they or some of their classmates are still sneaking cigarettes outside the schools and, from time to time, in the bathrooms. But some said the ban, coupled with growing peer pressure against the habit, has prompted many students to stop smoking.