His appearance is striking with a bushy Afro and a medallion around his neck. His rhetoric is emotional with chants and rhymes, shouts and occasional clenched-fist salutes. The response he gets from his audiences is often fervid.

But the impact Jesse Jackson has is uncertain. It is slight, his critics say, because the emotional effect of his speeches wears off relatively few of those who hear him change much of what they do.

But Jackson and his supporters believe his impact has been considerable, particularly on education where his emphasis on discipline, achievement, and standards of performance has become part of a widespread turning away from the stress on openness and creativity that was the dominant strain of education reform in the late 1960s.

Jackson also rejects the arguments made by some black activists, including former D.C. School Supt. Barbara Sizemore, that block students should be measured by different tests and standards than whites.

"There's a new quest for competence on the school scene," Jackson said last week during one of his frequent visits to Washington. "I think much of it comes from what we have been doing."

Although he lives in Chicago, Jackson has been coming to Washington regularly for the past 18 months.

Operation PUSH (People United to Save Humanity), the Chicago-based organization he heads, has established a national office here, dealing with national and international issues and frankly trying to get attention from Congress and the news media. With somewhat less success PUSH has tried to build a strong local organization in Washington.

On Friday Jackson spoke at graduation exercises in the Kennedy Center for students from Coolidge High School, 5th and Tuckerman Streets, NW. He congratulated them, like most graduation speakers do, but then added: "Maybe the biggest fraud going on in America today . . . is that many students are being graduated from high school and getting a diploma, but they have no information and they can't read well."

"When that happens," he said, "you better know that you have been robbed."

This year Jackson also was the graduation speaker at Parkdale High School in Prince George's County. Last year he spoke at 10 high school graduations in the Washington area and appeared at about a dozen local school assemblies as part of his Washington organizing drive.

PUSH now claims to have about 1,000 members in Washington (who pay $5 a year in dues) but the organization has done and said relatively little about local issues.

Its chairman, D.C. City Councilman Jerry Moore, said the group is about to start a major drive in education, trying to get 50,000 parents to sign their children up for standardized tests that PUSH would pay for and administer, probably in churches.

"Many parents simply don't know where their children stand in reading and arithmetic," Moore said. "If they find out they are way below grade level, we hope they will seek the kind of help at school that is necessary."

"This isn't a program to embarrass the school system," Moore said, "but we do think parents should know how well their children are doing, and then get behind their children and make sure they do better."

D.C. School Supt. Vincent Reed said he has not been told about PUSH's testing program, but he said he agrees with what Jackson and PUSH are trying to do in the schools.

The Washington school system Reed said, is working on its own competency-based curriculum, drawing up lists of skills and information that students should know at every grade. By 1980, Reed said, students will no longer be promoted or graduated unless they achieve at a minimum skill level.

Meanwhile, PUSH has drawn up its own suggested list of skills of what students should know in English, mathematics, and other subjects before they graduate from high school.

"I think we're walking in the same steps," Reed said, "There's no doubt about it."

In addition to having a similar outlook, there is one other tie between Jackson and the leaders of the Washington school system: Dr. Therman Evans, the president of the D.C. School Board, is the national medical director of PUSH. The position is unpaid, but Evans often travels with Jackson and speaks of him warmly.

Moore, the chairman of PUSH's Washington chapter, is a Republican, and Jackson's emphasis on morality, discipline, and academic standards has drawn praise from many conservatives. But Jackson's own views on economic and political matters are clearly to the left - against high defense spending, in favor of federal health insurance, guaranteed jobs, high taxes cn business and high benefits for the poor.

A Baptist minister, Jackson, now 35, was a close associate of Martin Luther King Jr. in many of the major civil rights campaigns of the 1960s. He headed King's Operation Breadbasket in Chicago, leading boycotts against some white businesses, and was present in Memphis when King was shot in 1968.

He found PUSH in 1971 after splitting off from the Southern Christian Leadership Conference headed by the Rev. Ralph D. Abernathy.

Frank Watkins, the group's public information officer, said PUSH now has about 40,000 dues-paying members, about 95 per cent of them black. He said about half live in Chicago, where Jackson and PUSH have become a conspicuous force, though at odds with the city's dominant Democratic Party machine.

"I would love nothing more than to have 50,000 people marching in front of Congress for national health insurance." Jackson said in an interview last week, "or for the Humphrey-Hawkins (full employment) bill, or to have 50,000 people outside the U.N. demonstrating against American support for apartheld (in South Africa). But they won't come out."

"What does it matter if I am a general of an army, raising the radical issues," he continued, "if the people are home looking at television or in the parks getting high."

Since the late 1960s, Jackson said, "the whole agenda (of many American students and blacks) has shifted to the pleasure principle and self-gratification, instead of social emancipation."

"They're fighting for the right to lower the liquor drinking age," he continued, "the right to smoke marijuana, the right to live together and not be married, the right to have unnatural sex mates . . . .The biggest abomination is to call those things civil rights.

"There will only be social change," Jackson said, "if there is a cultivation of self-discipline and a pursuit of excellence in the schools and everywhere else. There won't be any change as long as the pleasure principle prevails."