If they are to make ends meet, school committee members and the public schools superintendent will have to cut $1.9 million dollars from the proposed 1986 school budget.

Among the possible budget cuts are proposals which could mean eliminating 40-50 teaching and nonteaching positions, combining grades in the city's 13 elementary schools, and reducing alternative high school programs.

Since mid-February when Superintendent of Schools Robert J. Peterkin first proposed the budget, the School Committee has held several open hearings on the budget and ways to trim it.

Peterkin's original reduction proposals, which will be revised this week based on school committee comments, called for the elimination of 44 positions, including 30 teaching jobs and several education programs.

Lay-Offs Hurt

"Ninety percent of the teaching reductions are painful and undesirable, but they're choices for which there are few alternatives," said committee member Glenn S. Koocher '71.

Attrition and faculty leaves "may make up for some, but not all of the reductions," said Peterkin. "If it's even one person, it will hurt."

But even after attrition and paid leaves are taken into consideration, at least 25 teachers will be forced to take unpaid leaves or be laid-off, said Koocher.

"People who provide direct services to the students should be the last ones affected" by the cuts, said budget subcommittee chairman Jane F. Sullivan. She added that she hoped fewer than 20 people would be laid-off.

Because salaries and benefits make up almost 75 percent of the budget, and since the nonsalary items are mostly fixed (such as energy costs), teaching and other school employees, must bear the brunt of the cuts, said Oliver S. Brown, assistant superintendent for planning and management.

Representatives of the Cambridge Teachers Association could not be reached for comment yesterday.

Because Cambridge has a policy of not firing minority teachers until they make up 25 percent of the faculty, nontenured, white teachers are the most vulnerable to lay-offs, said Koocher and Sullivan.

Minority teachers currently make-up 15 percent of the faculty, according to Koocher. Forty-six percent of the students enrolled in Cambridge public schools are non-white.

Tightening Special Belts

In cutting the budget, Peterkin said he will "avoid the mindless, across-the-board mentality... there will be some tightening but no destruction of programs."

For example, the committee will consider eliminating a guidance conselor in the pilot school a; Can. bridge Rindge and Latin High School, a program designed to bring 200 students into close contact with 10 teachers and advisers.

Students in this program have the highest SAT scores in the city, said Ray F. Shurcleff, dean of the school, where 75-80 percent of the students go on to college.

The loss of a guidance counselor, however, would "cripple the program's integrity," said Shurtleff, because the counselor's workload could not be redistributed to already overworked instructors.

Cutting the budget may also involve combining grade levels--so-called multigrading--in classes with fewer than 21 students to reduce the number of teachers.

City Councilor Alice Wolf, who served on the school committee for eight years, said she did not object to the concept of multigrading, but that it was not the way to cut the budget.

Wolf said multigrading had the potential to be a good way of teaching, but "if it's imposed on teachers and parents who are opposed to it, then it's a problem."

Officials attributed the budget shortfall to inflation, decreasing state aid, and Proposition 212.

In addition, two large creases--for administrators and teachers--have contributed to the projected deficit.

While Koocher blamed much of the budget problem on this item. Peterkin and school committee members Frances H. Cooper and Rena H. Lieb said the salary raises--18 percent for a small number of administrators and 9.5 percent over two years for teachers--only keep up with inflation and should not have been any lower.