"My advice to Harvard students," Al Franken said soberly, "is to drop out."

It was hard to tell whether Franken was serious or not. His round, plump face certainly looked sincere, and with the aura of innocence radiating from his big, thick glasses and curly hair, who would have doubted him? He was, after all, a 1973 Harvard alumnus himself, so he should have known something about the value of his Psych and Soc Rel degree.

But something wasn't quite right. Franken was sitting in his writing office for "NBC's Saturday Night," a new, New York-based television comedy show. And that chair Franken was sitting in--that was the chair he is paid to sit in and make jokes.

A few yards away, another writer was playing a joke on Jane Curtain, an attractive "Saturday Night" actress. The writer had taken a surgical glove and stretched it tightly across the top of a quarter. The coin stuck to the underside of the glove, but the rubber was so thin that the quarter appeared to be sitting upon it. He walked over to Curtain's desk and pressed the top of the quarter, which fell magically to the desk, and the writer walked away giggling, leaving Curtain to try to find a nonexistent hole in the glove. "Stupid trick," Curtain shouted as she poked the coin at the rubber. "What a stupid trick."

Something was rotten on the 17th floor of Rockefeller Center.

Finally, Franken's stoic expression collapsed and he broke into laughter. "I'd like to see something like that in The Crimson," he said. "But seriously, if anyone wants to make it in show business, well, it doesn't help at all to go to Harvard--not at all."

He learned back in his plush chair and grinned because he knew he had made it, for a while at least, despite his four years at Harvard. Nine months ago he had his big break, when "Saturday Night" producer Lorned Michaels discovered Franken and his partner, Tom Davis, in a Los Angeles nightclub and hired them to write for the live, 90-minute comedy.

Since then, "Saturday Night" has be ome the most talked a out show since "Laugh-in." Its ratings have consistently climbed, and the waiting period for one of the 200-odd tickets to see it live is over four months. Several of the regular actors, who bill themselves as "The Not Ready For Prime Time Players," have received offers for movie or situation-comedy roles. The standout comedian, Chevy Chase, is considered the heir-apparent to Johnny Carson ("The Tonight Show"). And "Saturday Night" has done all this at a fraction of the cost of a six million dollar woman.

"Since it's my first television job, I had to settle for whatever they could give me," Franken said. "It pays O.K., Tom and I are learning a lot, and it's gratifying to see our stuff done on television."

He broke into a grin again, recalling his high school dreams of a show business career. Franken and Davis first began writing together at Blake, a Minnesota country-day prep school, not for comedy skits or plays, but for morning chapel announcements. Although they didn't "hang out around the school theater," Franken said, they wrote together whenever they could gather up enough energy to put on a show. When Franken graduated from high school in 1969, he had Physics in mind for a concentration--"I was good at math and all that stuff"--but show business dreams were far from forgotten.

"I never even took a single Physics course at Harvard," he said. "I had a real crisis freshman year, I just didn't know what I was going to do. I guess I always wanted to do an act with Tom." Franken paused to wave to Michaels and actress Gilda Radner as they passed by the office door. "Anyhow," he continued, "my partner and I worked together for a couple of summers. I guess it was the ones between my sophomore year and my senior year. We were really lucky, we got booked in a place in Minneapolis. Our stuff was good, but our performing was so terrible." By that time Davis had quit the University of the Pacific, and Franken's show business dreams had overtaken his physics plans.

He turned to a vocational aptitude test for reassurance. Sciences came in near the bottom, while Camp Counselor finished first. Counselor was immediately ruled--"I can't canoe or anything." Runner-up Music Performer was equally unattractive because he can't play any instruments. "Speech came in third," he said. "I figured show business was close to speech."

So, knowing he would not be a psychologist, Franken spent most of his time at Harvard getting from one day to the next, always careful to keep his head above academic water. He spurned the Loeb, the Lampoon and the Pudding to work by himself for Dunster House productions.

"The Loeb, well, that's theater," Franken said, frowning a bit. "I was just never into theater. I was interested in real show business. And the Lampoon--it wasn't just that I didn't like them, I thought the stuff they were doing was terrible."

He recalled writing a skit called "Seamen on Broadway" that was rejected from the Hasty Pudding show "by some preppie so they could take some other preppie's skit." Franken started to smile again, but his tone was serious, too serious. "It's not preppies, cause I'm a preppie myself. I just don't like homosexuals. If you ask me, they're all homosexuals in the Pudding. Hey, I was glad when that Pudding homosexual got killed in Philadelphia." The smile became so broad it pushed his eyes shut. He couldn't stand it any longer. "Put that in, put that in," Franken laughed, leaning over the desk. "I'd love to see that in The Crimson."