Only four months after the District's school board and superintendent lauded recent midterm promotions as a sign of improving elementary education, school system administrators are calling the three-year-old promotions policy an experiment that failed.

At least half of the board members said they are leaning toward returning to annual promotions for elementary school students despite the fact that 84 percent of the city's elementary school students received midterm promotions last January. Superintendent Floretta D. McKenzie told the board last Wednesday that the promotions policy "has not worked effectively."

Meanwhile, some parents and PTA leaders question the wisdom of dropping the policy when results are promising.

"We would not be dropping any standards," said board member Linda W. Cropp (Ward 4), chairman of the board's educational programs committee. "When we went into this, we embraced it because we needed to do something, but we should have the flexibility to change things when needed, and midterm promotions are too cumbersome."

Half of the school system's 21,622 first through third grade students had failed at the midterm point in the 1980-81 school year, the first year of the program. Former Superintendent Vincent E. Reed heralded the program then as the way of ending social promotions and forcing children to master basic math and reading skills. Last January's promotion figures, according to McKenzie, showed that students had begun to grasp the new standards and show dramatic improvement.

But McKenzie, James Guines, associate superintendent for instruction and the school board's educational programs committee all say those same higher standards can be maintained without burdening teachers with enormous paperwork at the midyear point, and without "stigmatizing" youngsters by labeling them as failures only four months into the school year. McKenzie added that there are not enough resources to implement the plan fully.

"We have looked at this situation very carefully. We have given attention to how to untangle a 12-step promotion process," said McKenzie. "I want to assure the board that we do intend to give attention to the needs of students at the midyear point without a promotion policy."

Under the program, students must master 70 percent of their particular grade level's math and reading skills. Students in first grade reading classes, for example, must be able to write rhyming lines, give opposites of words and identify relationships. Those students who fail receive special tutoring and attend after-school programs.

When Reed was superintendent, he said he was faced with some high school graduates whose grasp of basic skills was so poor that they had trouble coping in adult life. Last week, Reed said he implemented the unique program as a way "to make sure we don't have kids going too far before we realized what their deficiencies are. I did what I thought was best for the system at that time. Flo has to make the same assessments I did. Whatever she does, I support."

But others interviewed, especially parents and PTA members, were not so amenable to the idea, saying that the students have shown improvement and that teachers shouldn't complain about added paperwork. On the other hand, instructors and leaders of the Washington Teachers Union say the idea of going back to annual promotions is great.

"We may be losing a valuable feature of the student progress plan. The grown-ups have failed to provide the resources to make this program work," said Phyllis Young, past president of Parents United for Full Public School Funding, a local group that lobbies for more school money.