Acting D.C. School Superintendent James T. Guines announced yesterday that Operation Rescue, the volunteer tutoring program for students who failed to be promoted in January under the system's new promotions standards, helped to improve the youngsters' performances dramatically in the second semester.

Guines said that in the 40 schools where the program operated, two-thirds of the students who failed in January are now going to pass.

It could not be determined yesterday if the tutoring program alone was responsible for that improvement, because there were no statistics on how well students in the schools that participated in the project improved in comparison to students in other schools.

Guines, nevertheless, said he felt "Operation Rescue did make a big difference" and announced his intention to continue the program next year.

The school system turned to the volunteers last February because it had no funds to hire additional teachers to help the failing students.

The system is expected to lay off at least 200 more teachers this year in order to keep within the confines of the budget the mayor and City Council has approved for the schools.

The 12,000 Operation Rescue volunteers worked in those elementary schools that had the bulk of the failing students. Guines said that 2,454 youngsters in those schools failed at the end of the second semester compared with 6,264 youngsters in those same schools who failed at the mid-year point in January.

The program itself received these high marks from the tutors and their principals, according to a survey taken by school officials:

Seventy-four percent of the tutors interviewed rated the program good to excellent.

Ninety-two percent said they would volunteer again.

Most principals interviewed in the survey felt the program "brought positive elements into the schools," helped the students develop more positive self images and "showed people outside have a concern for the schools," the survey concluded.

More than half of the tutors lived in the District, but traveled almost an hour from their homes to the schools where they were tutoring, the survey said. About 25 percent of the tutors were retired persons.

Many more students failed this year than in prior years as a result of new mid-year promotion standards introduced last September in grades one through three. These standards required students for the first time to master specific skills in reading and math before being promoted to the next grade level in January and June.

"This has not been an easy year for us," Guines said, referring to the constroversial promotions standards, the unexpected retirement of Superitendent Vincent E. Reed and the massive teacher layoffs. But, he added, "We have been very successful in turning the system away from possible movement back to chaos to one which will continue its pattern of academic excellence."

Guines, who is among the contenders for appointment as Reed's successor, also said he plans to keep to Reed's plan of introducing new, stricter promotions standards in grades 4 through 6 next Septmeber.

While Guines was congratulating the volunteer tutors yesterday in the auditorium of Roosevelt High School on 13th Street NW, Mayor Marion Barry was in the cafeteria of the Gordon Adult Education Center in Georgetown, thrashing out questions over the schools' diminishing budget with some 50 representatives of parent-teacher associations.

There, responding to a comment from a parent about the quality of D.C. public school teachers, Barry said that despite the number of committed teachers in the city, the competency of D.C. teachers could be improved.

Barry also said he felt teachers in general are less committed to their profession and their students today than in the past.

Barry told the parents he had no foreknowledge of an effort in Congress to give the mayor line-item control over the budgets of various city agencies, including the school system. He added that he did not wish to have this authority even though it would give him greater control over agencies that have overspent their budgets in the past.

"He feels that would just create a new bureaucracy," Dwight S. Cropp, Barry's executive assistant, explained after the meeting.

Barry's meeting with parents, the first of its kind, was cordial despite harsh and frequent crticisms many parents have made of Barry's efforts to cut the school budget, according to Patricia Morris, president of the D.C. Congress of Parent-Teacher Associations.

Barry also said he wants to ask the heads of universities in the city to offer volunteer services to the public schools, such as tutoring. He said the tax exempt private universities "should give some services to the city."