The creator and star of the series about the high school adventures of the Sweathogs appeared in only two episodes that season, citing what he calls ìcreative differencesî with the writers and producers. John ìBarbarinoî Travolta also appeared only occasionally, but he was on his way to superstardom in the movies.

Kaplan was just disgusted, and he was on his way to a very different kind of life.

ìIn that last season, the guys were too old to be in high school anymore. I wanted them to move on to junior college. I mean, they were in their late 20s and it was starting to look ridiculous. I think it would have lasted a long time if the series had been updated, like Saved by the Bell. But they just didnít want to do it,î Kaplan said recently in a phone interview from his Los Angeles home.

So, missing its biggest talents, Welcome Back Kotter failed badly in the ratings and was canceled. Travolta went on to movies such as Grease and Saturday Night Fever. Other TV series that premiered the same year as Kotter included Laverne and Shirley, One Day at a Time and Phyllis. Originally on Tuesday nights, Kotter followed Happy Days.

Kaplan, 33 at the time, went on to star in another, short-lived TV series, Lewis and Clark, and to make occasional appearances in movies.

But mostly he reassessed his career and became a businessman, an investor who put his considerbale energy toward what he refers to in interviews as ìfinancial things.î

Along the way, he hosted a radio call-in sports show in Los Angeles and won a few national poker tournaments. The former remedial high school student from Brooklyn did quite well for himself and was content until something else happened recently.

Nickelodeon began showing reruns of Welcome Back Kotter on Nick at Nite; Kaplan and some of the Sweathogs taped promotional pieces for the show helped the Class of Kotter Culture to seep back into the national consciousness.

Bolstered by that new interest, Kaplan began to revive his original career as a stand-up comic, which will bring him to Snickerz Comedy Club on September 1 and 2.

Not that the show had ever really gone away. While not exactly Masterpiece Theater, Kotter had struck a nerve in the national audience. Perhaps helped by the pleasantly wistful theme song which briefly revived the career of John Sebastian (who has managed to avoid any resurgence of interest), Kotter became one of those TV shows that everyone remembers, and Kaplan one of those TV stars who never quite fade from memory.

ìPeople still recognize me, although sometimes they think Iím a teacher they had once. They say, ëDidnít you teach at Saint Francis or something?í For some reason, Kotter became part of the pop culture, something other, more successful shows did not,î Kaplan said.

And it still feels good to be part of that. ìI think we did something right. The relationship, the distinctness of the characters, was something people remembered. Itís not something you can plan on, or it wonít work out. The people who made Rocky Horror Picture Show didnít think it would become a classic. When they tried to make a sequel, it played like one night,î Kaplan said.

The characters in the show were based on classmates of Kaplanís when he was in high school, and perhaps audiences sensed they were something more than glib creations of Hollywood writers.

The showís premise, in turn, had grown out of Kaplanís comedy act, long set pieces on how tough the real kids were (How tough? ìThe gangs didnít shoot you. They inserted the bullets manuallyî).

Now that heís back on the road, Kaplan is still doing longer routines instead of one-liners. The material no longer dwells on high school, however, because, after all, weíre all getting long in the tooth.

After trying his act out in New York, Los Angeles and Florida last year, Kaplan has worked on new material this year and is expanding his tour. He has found at least one change over the years: Comics now tend to do one-liners, and itís a challenge to get people to listen for four or five minutes, when one joke sets up another. Heís confident it will work.

ìI get all ages, but a lot of people 45 and older. If someone can do intelligent comedy, talk about their life experiences, the older people are looking for that. With the kids, itís the differences between generations. How people react to current fads, talking about the political scene and whatís going on there,î said Kaplan, 54.

Not that people donít ask about Kotter. And Kaplan is happy to oblige.ìI talk about the TV guys, the characters they were based on, how different the TV characters were from the real ones. They kept toning down the TV version, like three of four times. It was supposed to be a funny Blackboard Jungle, but it got down to the point where there was nothing menacing about them at all,î Kaplan said.

The characters included Juan Luis Pedro Phillipo de Heuvos Epstein, Freddie ìBoom Boomî Washington, Arnold Horshack and Vinnie Barbarino, and their teacher who returned to his old high school, Gabe Kotter.

One night in 1974, Kaplan had been doing his act at The Comedy Store on Sunset Boulevard, on the same bill as Freddie Prinze, another comic who would go on to portray himself on TV, but with very different results (he committed suicide).

Producer Alan Sacks, a former Brooklynite, saw the show and loved the reminiscences about the kids in New York. He and Kaplan had lunch, and came up with the idea of a teacher to those same misfits.

Itís hard to believe now, but the show was something of a controversy, largely because people feared the irreverent treatment of adults by the Sweathogs. Kotter was banned by the ABC affiliate in Boston for a time, and the National Education Association insisted on having an ìadviserî on the show to protect the image of schoolteachers.

Nothing to fear, of course. As the seasons progressed, the show relied more on slapstick and jokes than on cutting-edge comedy. Kaplan wrote a couple of shows a season, and learned acting techniques from his TV students ó all of whom were veterans of the New York stage.

ìThey taught me about acting and I taught them about comic timing, when to wait because they should expect a laugh,î Kaplan said.

Recently, Kaplan discovered the writers on show, including himself, own the rights to any movie version that may be made. Now, he is ìseeing if people might be interestedî in Kotter: The Movie.

If they did it as Kotter 2000, I would be in it,î Kaplan said. ìIf they wanted to do it as Kotter in the 70s, theyíd have to get someone younger.î

If he has one regret about the show, itís that he failed to obtain a guest appearance by his hero, Groucho Marx. The idea was for Kotter at the end of a show to approach an old man waiting for a bus and say to him, ìAs long as weíre both waiting, let me tell you a joke.î Then the old man was to turn around, be revealed as Groucho, and reply, ìThatís the worst joke I ever heard.î

In real life, Groucho had asked Kaplan to tell him the joke planned for the scene. Groucho listened, smiled, and replied, ìThatís the worst joke I ever heard.î

Alas, the nurse/guardian who took care of Marx in his later years demanded too much money, and the appearance never happened.