Andy Young, looking as urbane and confident as only a mayor-elect and former U.N. ambassador can, came back to his home away from home with a bit of heavy baggage on his mind.

"When students copped out they got screwed," Young responded last week when asked about cutbacks in federal student loans at a luncheon with Montgomery College students and faculty. Young, who had been invited to address the Rockville campus, fielded questions for about an hour with a small group of student leaders before taking to the gymnasium podium to address a larger audience of 500.

Although Young had started the round table repartee with the statement, "I would like to know what you're thinking," there was little doubt as to whose mind the students were interested in foraging. Nearly 99.99 percent of the discussion was devoted to the past, future and present thoughts of the next mayor of Atlanta.

It wasn't always the most heartening of discussions.

"Students didn't vote in the last election . . . and I'm not going to subsidize student apathy and Reagan isn't either," Jimmy Carter's former U.N. ambassador said, when asked if he had any plans to free money from Atlanta's coffers to offset massive federal cutbacks in student loans.

"There's no need in studying political science if you're not going to vote," Young said.

Though only miles from the hobnobbing of Washington and its fare of national and international events, the students at Montgomery County's largest junior college still seemed awed by Young's prominence. Give-and-take in the discussion was limited as the nodding but silent group dipped quietly into the cherry-topped chocolate cake. Few questioned Young and even fewer approached him before or after the lunch. Young, most seemed to agree, was the nearest thing to a full-fledged celebrity the campus has had as a guest in a long time. His visit cost the students $6,000.

So when Young spoke, students listened.

"The best lessons students can learn this year is that when you don't vote it hurts you," Young said, reminding his listeners that most of the student programs, including the 18-year-old vote, were implemented from 1966 to 1976 during periods of student activism.

"I can guarantee you that if there is massive student registration on campuses this spring, Congress will instate those student loans. We have a system that responds to pressure," said Young.

"You've got to wake up and take care of yourself. Your mama didn't change you until you hollered and she loves you."

Later the student body president, 35-year-old William Starr, praised Young for his candor and agreed with his assessment of current student involvement.

"Students are their own worst enemies," said the lanky native of Norfolk, Va. "They want to blame the administration for all their problems. . . . Young realizes that won't work. They need to hear that."

During another portion of the round table discussion, the new leader of the city that calls itself "too busy to hate" cautioned the students against casting all problems in color.

"Race is a dominant factor in our society and almost everything you do is going to have some racial undercurrent, but I am no less threatened by that than by sexual challenges," said Young, who claimed the victor's wreath in one of Atlanta's most race-dominated mayoral elections.

"I think we're on a completely different level of race relations now than we were in the '50s and '60s, but it may be more sensitive now because we're closer together," Young said, discussing allegations that the Reagan administration is insensitive to race problems.

"The more you change things in society the more you're going to have to change," Young said. "And when race becomes an added factor we usually want to oversimplify a very complex situation."

"The things about the lunch counters were really trivial," said Young in reference to sit-down strikes by blacks in the early '60s protesting segregation practices. "They didn't require any personal sacrifice or change.

"But when you're talking about people competing for a declining number of jobs, that's going to be far more tense in a declining economy than, say, integrating lunch counters."

Still the diplomat, Young deflected a question from the back of the room about his political ambitions post-Atlanta, insisting as he did to his doubters during the recent election that a man who had played a major international role could be satisfied with the job of getting the garbage trucks to roll.

"I don't think there is any such thing as going up or down in politics," he said.