D.C. School Superintendent Vincent E. Reed has proposed the layoffs of hundreds of teachers and other school personnel, increases in the number of pupils per class and reductions in the prekindergarten and adult education programs for the 1980-1981 school year.

The proposed cuts are necessary, Reed said yesterday, because Mayor Marion Barry and the City Council have approved and sent to congress a school budget that is $27 million less than the school system needs for the coming year.

"It's the worst [budget crisis] I've seen since I became superintendent" in 1975, Reed said.

Reed's plan calls for cutting 893 jobs, with more than 700 of them teaching positions. Salaries represent 88 percent of school system expenditures.

School administrators often propose layoffs or reductions in programs in an effort to bring pressure on local governments to restore budget cuts, but the District school system has never in recent years threatened to lay off so many teachers or cut back so massively on programs.

However, the city is facing an anticipated $172 million overall budget deficit for the current fiscal year and is not expected to alter its austere budget proposals.

Reed said he believes half of the teaching jobs he proposes to cut can be eliminated through attrition.

Nonetheless, the dismissal of hundreds of teachers, aides or other school personnel would constitute the first general layoff of school personnel in at least seven years, Reed said.

If approved by the school board, the cuts would go into effect Oct. 1. the board's finance committee is scheduled to consider Reed's proposals Monday.

Reed said one justification for cutting the number of teachers is a projection that 99,000 students will be enrolled in the public schools in the next school year -- 7,500 fewer than this year.

There are 6,600 teachers in the system now.

The school system could save more than $16 million by cutting back on the number of teachers next year, according to Reed's plan.

Reducing the number of teachers would increase the pupil-teacher ratio in grades one through six from 26 to 1 to 28 to 1, Reed said.

To save about $1.7 million, Reed has also proposed cutting back the prekindergarten program for 4-year-olds from all day to half-day. The District is the only local government that provides such a service.

"Since the majority of parents sending children to public prekindergarten classes are working, many will be required to seek private all-day programs," Reed said in his proposal. "Once the children are in private facilities, many may not return to the public school system," he said.

Reed has also recommended cutting back the number of community schools from 16 to 11. These schools provide adult classes, such as typing and art, in the evenings.

A total of 9,787 students are enrolled in the adult education classes.

Reed also proposes cutting 30 positions in the system's central administration, ranging from employes who handle payroll to curriculum supervisors.

In addition, two of the school system's six regional offices would be closed. These offices were opened a few years ago to ensure that the school administration would be more accessible to the communities it serves. A total of 40 regional positions would be eliminated.

Reed said the net effect of the reduction of administration personnel would be "devastating."

He said the proposed administrative cuts would increase the amount of time it takes the system to respond to inquiries, reduce the number of training programs for personnel and cause delays in procuring services from and paying outside vendors.

In making any employe layoffs, the administration will consider the particular job an employe performs and whether there is a shortage of employes in that category as well as seniority.

The superintendent and his staff scrapped over other budget-cutting alternatives, such as shortening the school year and closing schools.

The school board's finance committee, meanwhile, has agreed on a plan to deal with the anticipated shortfall of $26 million in the current fiscal year's budget. Without cutting back on major programs, the finance committee was able to find ways to save $19 million mainly by keeping some positions vacant and reducing staff.

John E. Warren, head of the finance committee, said the committee had identified other areas where the school system could save an additional $4 million, but has not yet taken a formal vote on these cuts.

The finance committee has so far chosen to ignore the mayor's order to cut an additional $6 million from this year's budget as part of his effort to reduce the city's overall defict.