As a police crackdown on marijuana use at Montgomery County high schools continued yesterday, county officials produced a plan designed to make it eventually unnecessary for police to keep schools under surveillance in anticipation of drug arrests.

The arrest of 12 students at Gaithersburg High School on marijuana possession charges yesterday brought to 65 the number of students arrested outside their schools during the past week and a half.

County Executive James P. Gleason said yesterday he agrees with the arrest, but "I don't think it's a healthy situation for police to do permanent surveillance of school environment, the climate, should be one that is free and relaxed and in students' minds should be geared to education."

Gleason asked school officials to announce a plan to curb marijuana use, and, after Gleason, Police Chief Robert J. diGrazia and School Superintendent Charles M. Brenardo met to discuss the plan, Bernardo announced these provisions:

School officials will be meet with student leaders, who will be asked to speak to other students in an effort to discourage drug use. "We want student leaders to generate peer pressure on other students so the youngsters discontinue drug use to (avoid harming) the image of theschools," Bernardo said.

Elementary school pupils will be given classed on drug abuses in an effort to form attitudes against drugs before high school.

"Student behavior with drug use is not greatly changed at the high school level when attitudes are already formed," Bernardo said. "If education about drugs doesn't make a big impact on the high school level we should take a look at intensifying education for younger students about drug use an abuse."

Additional training will be sought for building monitors - school employes who make sure that students go to class - to make them better able to identify drugs and drug use and to equip them to act as counselors for students who want to stop using drugs. School Board approval will be needed to raise the monitors salaries.

School officials will ask parents to cooperate in educating students to the dangers of drugs.

Bernardo said he supported police in their arrests of students who smoked marijuana on or near school grounds. "We have to make it clear that the school is not a sanctuary for drug use. When students violate the law they must bear the consequences," he said.

High school principals and school board members generally expressed agreement with the intent of the plan but some called some of its provisions idealistic.

Wheaton High Principal Eugene Moran said it might be difficult for student leaders to influence other students against smoking marijuana. "Fear pressure is very strong," he said. "How much effect a student governmnt type would have on someone in the drug culture is another ball of wax, another issue."

Moran applauded the plan to give building monitors better training in detecting drugs, but he said their role should be restricted to enforcement and not expanded - as the plan suggests to counseling students. "We have regular counselors and our teachers are trained as counselors. The hall monitors should call the shots. There has to be someone who stops counseling and starts administering."

School board member Marian Greeblatt said the plan did not try to attack an important reason for drug use - boredom. She said students, particularly in the suburbs, have too few activities after school. She suggested that more programs be started for students in recreational centers.