Some people embark on second careers after they retire. Few make as dramatic a transition as Jack Rothman. The 80-year-old former college professor is now a standup comic, and he tells Mike O'Sullivan that making people laugh fulfills a lifelong dream.

A funny thing happened to Jack Rothman after he left teaching. A retired professor of public affairs at the University of California, Los Angeles, Rothman has always loved humor, from puns and jokes to funny stories. One day, his grown children offered a suggestion.

"Well, at my 75th birthday, my kids decided to give me a certificate to take a standup comedy class," he explains. "You know, I can't say exactly why. Maybe they were saying, hey dad, you're walking around the house trying to be funny. Why don't you really learn how to do it?"

He was soon performing at comedy clubs around Los Angeles.

The comedian jokes that the comedy is easy, but at 80 years of age, standing up is tough. Much of his humor is about seniors.

"Since retiring, I discovered that senior citizens don't get any respect," he says. "For example, you hear it all the time. 'Those old geezers, they get into the movie for practically half price.' Well, we ought to. We sleep through half the movie. We ought to get in free. The other half, we don't hear."

He jokes that many young people complain about older drivers. He rejects the criticism.

"That's a lot of bull. Do you think it's so damn easy to maneuver a car on the sidewalk?" he asks.

Rothman says too much comedy today aims at easy laughs through crude and stupid humor.

"You have four-letter words, you have dangling body parts, you have body noises. I don't go for any of that," he says. "My comedy is straight and smart. I practically lean in the other direction to balance things out."

He says his model as a comic is the late Jack Benny, a gentle performer who never insulted his audience.

Rothman finds that even youthful audiences respond to his jokes. He recently faced off against nine younger comics in a comedy competition, and was voted number one.

In his academic career, Rothman was as an expert on community organizations. He wrote 25 books and helped students understand the dynamics of civil society. Today, he performs standup routines for community organizations as part of a comedy trio, with two middle-aged colleagues. They call themselves "Baby Boomers Plus."

"I'm the 'plus' in the trio, and we perform at grassroots organizations, civic organizations, service organizations, around the city - the Red Cross, some senior housing developments, things such as that," he says. "And the idea is to help make these organizations stronger and more effective by lightening up stuff, giving people some enjoyment."

The comic says when he was teaching students, he felt exhilaration when explaining a complicated point and seeing a glimmer of understanding in their faces. He gets the same exhilaration today standing in front of an audience and getting some laughs.