A new Montgomery County school policy requiring all school employees to complete a 45-hour black studies course before receiving promotions or certification to teach has angered union leaders and some school officials, who say the program will be counter-productive and too expensive.

The course, part of the school district's career education curriculum, has been offered to teachers, administrators and support personnel for the last three years, and by all accounts, has been well planned and well taught by the district's Human Relations Department.

Since 1975, all school employes have been officially required to complete the course. It was not until last week, however, that the Board of Education approved measures to enforce the policy.

Noting that only about 1,500 persons - out of 12,000 school employes - have finished the course so far, the board passed the new policy by a 4-to-1 vote. Under the new requirements, all beginning teachers will have to complete the course within two years of their employment, and more experienced teachers will need the course to advance to higher salary levels or to receive their 10-year certifications.

Board president Elizabeth Spencer says the requirement of the course is appropriate because "there is no one in the school system who can't benefit from a program like this." But board member Marian Greenblatt, who voted against last week's resolution, and school union officials say the policy is insulting to teachers and will cost the district too much in fees to substitutes hired to replace the teachers and other employes taking the class.

"Our objection is not to the course," said Henry Heller, president of the Montgomery County Educator's Association. "We object to the board dictating how teachers should spend their lives. They're making a value judgment that this is worth 10 percent of a teacher's time. And it's a knee-jerk reaction - we have a problem so let's make the teachers take the course."

Eleven sections of the course are being offered in Montgomery schools this semester, and 15 will be offered in succeeding semesters. Classes are conducted by school staff members - ranging from human relations employes to assistant principals - who have been trained for the work.

The course requirements are fairly stiff: 1,500 pages of reading in three different textbooks, several reports, and a final examination. No grades are given, however, and participants are required only to show up for 13 of the 15 three-hour class meetings to fulfill the black studies requirement.

"There are a lot of people who dread the course, who don't like the idea of all that rading, or the exam," said Judy Docca, the program's coordinator. "But once they get into the course most of them are pretty happy about it."

"In a lot of cases, people will feel free to talk about things that have been on their minds for a long time about racial relations," Docca said. "We've corrected a lot of misconceptions. We've never talked about race in the schools before, and a lot of teachers have misconceptions - stereo-types they picked up on the street - that need to be broken down."