D.C. school superintendent Vincent E. Reed approved a plan last night that would end automatic promotions for elementary school students and instead require the students to demonstrate mastery of specific skills before moving on to the next grade.

If approved by the school board, it would be the first time that the school system had set up citywide standards to determine whether a student should be promoted. Previously, promotions were left strictly up to the teacher, and students often passed on to the next grade simply because of their age.

"This should be the step that will end that," said Dr. James T. Guines, associate superintendent for instruction.

The program would go into effect next fall in grades one through three. In 1981, it would go into effect in all grades.

The plan is part of the school system's ongoing efforts to improve the generally low performance level of public school students. D.C. students consistently have scored lower than their counterparts in other local jurisdictions and below national norms in reading and mathematics. Some students have graduated from the city's high school without being able to read.

The school board is expected to react favorably to the plan. It was the board that directed the superintendent in 1975 to develop criteria for determining promotions, board president R. Calvin Lockridge said.

A unique feature of the plan is its call for an evaluation of each child at the end of the first half of the school year. Among the skills to be tested are being able to compare two numbers to determine which is greater, measuring the length of an object of centimeters and measuring a pint, quart and gallon.

If a first-grade student has mastered enough skills by the first half of the year, he will be moved onto a level called grade 1b. If not, he will remain in a group labeled 1a.

Students who remain in 1a will receive special attention and remedial work. Guines said, to bring them up to grade level by the end of the year.

Guines said details of how the plan will be implemented in the schools have yet to be worked out. In all likelihood, he said, students on level 1a would be mixed in with students on level 1b in the same classroom in same schools.

In other schools, the two groups of students might be separated into different classes, Givens said.

The teachers will be solely responsible for certifying whether or not the students have mastered enough skills to go on to the next grade level. Tests will be administered to all students in grades one through nine to determine as usual their achievement in reading and math, but the tests will not be part of the criteria for judging whether the student should be promoted.

Dr. Reuben Pierce, the regional superintendent in charge of schools in the Anacostia area who worked on the plan, said the tests will merely be an indicator of whether teachers are correct in their assessment of a student.

The idea of identifying students' weaknesses of the half-year is designed to prevent students from having to repeat a whole school year. If students do indeed need to repeat a grade, they will not have to go over the same material. Rather, they will be able to build on what they already have mastered.

Last week, Reed sent to the board another proposal for increasing the number of required courses for skills before they are awarded their diploma.

Guines insisted that the elementary school proposal does not represent a return to the old "tracking system," whereby students were rigidly grouped in classes according to their ability. That system was outlawed in 1967 after community activist Julius Hobson sued the school board and system, maintaining that once students were placed in a particular track, they stayed in it for all subjects until graduation.

"Tracking is a considerably different concept. It means placing students in a basic, middle or upper level," Guines said.

"Under the [superintendent's] proposed system, students will go from 1a to 1b, 2a to 2b and 3a to 3b. But if they were going from 1a to 2a to 3a, that would be tracking," Guines said.

The current citywide proposal is similar to a concept developed two years ago by Pierce and a group of principals from schools in the Anacostia area. The Anacostia region put into effect minimum standards for promotion in the 1978-79 school year. The Anacostia school region was the first to develop any system of minimum standards for promotion.

"We had agreed informally on some ( (SECTION) tandards . . . we've been waiting for some citywide system," said Joyce Jamison, principal at McGogney Elementary. She said the Anacostia region's elementary schools were not promoting first graders unless they demonstrated they can read a primer.

Harriet Murphy, principal of Janney Elementary in Northwest, said she saw the proposal as breaking down the stigma that comes with a student's being "left back."

Also, Murphy said, school systems are beginning to realize that there cannot be a timetable by which all students are expected to learn. "Some students learn rapidly, others take a little longer. That means we have to give them a longer time."

One teacher at Janney said parents often pressure teachers to promote their children, even if the youngsters are having learning difficulties. "This is a sticky issue with some parents, particularly fathers, who look upon [retention in the same grade] as failure."