Montgomery County residents are worried about discipline, the use of drugs and alcohol, and declining enrollment but still give their schools good grades, says the county Board of Education.

According to the recently released results of a survey of 436 adults, 66 percent rated schools with an A or a B. Only one flunked the school system.

School officials proudly compare these figures to a recent Gallup poll on nationwide attitudes toward education. Gallup's 1979 poll showed only 34 percent of Americans surveyed rated schools with an A or B and 7 percent failed their public schools.

In Montgomery County, 60 percent of those questioned at random by Department of Information staff members believe county schools are better than elsewhere. Residents also believe Montgomery students score higher than others on standardized tests and attribute this to the community's high socioeconomic level.

Although two out of three Montgomery County residents now do not have children in the schools, 94 percent believe good schools are crucial to attract new residents to the county, the survey states.

Discipline is the biggest problem schools face, Montgomery County residents believe, and in this they agree with their counterparts nationwide. Drugs and alcohol came in a close second with twice as many Montgomery County residents believing those substances are the school's chief ill than in the nationwide poll.

Concern about the problems caused by declining enrollment was a distant third, with 8 percent worried, compared with only one percent of persons polled nationally.

On a whole, the survey results show, Montgomery County residents believe the schools have good teachers and facilities and are pleased with the range of subjects taught.

But the residents surveyed want better discipline, more emphasis on basics, better teachers and smaller classes.

"We wanted to know what people thought of Montgomery County schools," explained Ken Muir, head of the school information department. "School board members, the superintendent and other school officials get lots of opinions from citizens, but they have no way of knowing whether these are isolated points of view or opinions shared by many.

The survey results, Muir added, will be the basis for issues addressed by the school superintendent in his next annual report.