Then:

Successful standup and onetime high school underachiever Kaplan 
o-created and starredas Mr. Kotter, a snarky teacher who returns toBuchanan High to school
the slacker Sweathogs. A former Sweathog himself,Kotter enjoyed a special bond with his Brooklyn class, sharing heartwarming life lessons and exchanges of rapid-fire banter.
 
 

ABC/Retna

After 'Kotter,' Kaplan shifted gears (and careers) to become asuccessful financial advisor. He later became a professional poker player and TV commentator for ESPN, among others. Still, Kaplan never lost the showbiz bug, continuing to do standup and reportedly developing a 'Kotter' movie musical.
 
 
 

Then:

After several small movie and TV roles, Travolta hit the jackpot playing Vinnie, a charming hooligan underachiever. Vinnie always got the girl and zinged his fellow Sweathogs with his trademark comeback, "Up your nose with a rubber hose!"
 
 

ABC/Retna

Travolta's post-'Kotter' career was a total roller coaster, from '70s superstardom ('Saturday Night Fever,' 'Grease') to a plunge in the '80s to a huge rebound with 'Pulp Fiction' in 1994. An avid pilot, Travolta owns five planes and continues to soar in Hollywood, starring in movies like 'Wild Hogs' and 'Hairspray,' with four films slated for '08-'09 release.
 
 
 

Then:

The clown prince of Sweathogs, Arnold Dingfelder Horshack seemed the
ultimate goof with his honking laugh and imbecilic cry of "Ooh, ooh, ooh!"
But he was actually the smart one, "graduating" for a time from Kotter's
remedial class to regular school, before returning because he felt out of
place being normal.
 
 

ABC/Retna

Typecast after 'Kotter,' Palillo got a nose job and straightened his
hair to land acting jobs -- with minor success. He portrayed Horshack in the short-lived '97 series 'Mr. Rhodes,' but primarily makes his living as a college drama teacher, graphic designer and book illustrator. Oh, and he threw his hat in the ring for 'Celebrity Boxing 2' in '02. "Ooh," indeed.
 
 
 

Then:

Epstein, full name Juan Luis Pedro Phillipo de Huevos Epstein, was the half-Jewish, half-Puerto Rican tough-guy Sweathog. Epstein bailed out of any school activity he didn't want to do by saying, "I got a note." The obviously phony notes were invariably signed, "Epstein's Mother."
 
 

ABC/Retna

Hegyes hopscotched through various TV guest shots, theater stints and small movie roles, including revisiting Epstein on 'Mr. Rhodes.'  He eventually
became a teacher in Venice, CA, and created and starred in a 'Kotter'-esque
delinquent-teen web series, 'The Venice Walk.'  He's a cousin to Jon Bon Jovi
and has six children from his four marriages.
 
 
 

Then:

Star hoopster Freddie "Boom Boom" Washingon was the jock Sweathog and the coolest of the bunch (he also worked as a radio deejay). His nickname came from his habit of playing air-bass.  Freddie was the most grounded Sweathog, though of course that wasn't saying much.
 
 

ABC/Retna

Despite roles in 'Death Wish,' 'Cooley High' and 'Roots,' Boom-Boom's career hasn't exactly been booming since 'Kotter.' Still, he kept his head in the game, working as a writer, director and composer while snagging the occasional plum role, like his turn as Papa Joe in the '90s TV miniseries 'The Jacksons.'  He also brought back his 'Kotter' character for 'Mr. Rhodes.'
 
 
 

Then: Pint-sized Principal Woodman railed against Kotter's permissive teaching methods and derided the Sweathogs with nasty putdowns like "they're not people." This being TV, of course, crusty Woodman had a secret heart of gold.

Now: An original cast member on the soap opera 'Search for Tomorrow' in 1951, White appeared on various TV series both before and after his grumpy-gus stint
on 'Kotter.' Sadly, he died in 1988 at the age of 69.

ABC/Retna

Then:

Thankless straight-woman to cutup Kotter and his Sweathogs, Strassman's Julie was the dutiful, dishy wife who endured hubby's endless stories about
his uncle Max and complaints about her "world famous tuna casserole" (secret ingredient: prunes). She remained faithful almost till the end, leaving just before the final episode.
 
 
 

The New York stage vet's post-'Kotter' career included TV shows like Magnum, P.I.,' 'M*A*S*H' and 'Touched by an Angel,' and work with the actors' union. She revived her sensible-spouse persona in the '89 hit film 'Honey, I Shrunk the Kids' and its 3D Disney theme park ride, and has appeared in TV shows 'Providence,' 'Tremors' and 'Third Watch' since.
 
 

David Livingston, Getty Images

Then: In a famous episode, Carlin was a cool underground radio DJ. He had
the Sweathogs on his station, KBAD, but they all clammed up. Except
Washington, who became an instant radio star.

Now: After decades of TV and movie roles, HBO comedy specials and voice work (like narrating 'Thomas the Tank Engine'!) Carlin passed away in June at 71, the most iconoclastic comedian since Lenny Bruce to the day he died.
 
 

Then:

As a preacher's daughter with an undeserved dirty reputation, this
brazen redhead found a way to knock the gossipy Sweathogs by pretending to be knocked up. Not exactly a women's lib moment, but hey, it's Brooklyn.  She'd later turn up as a stripper -- but this time with a twist: the Sweathogs helped her finish school.
 
 

ABC/Retna

Debralee left 'Kotter' after one season for a role on wacky '70s serial 'Mary Hartman,' and later appeared in the 'Police Academy' flicks as Mrs. Fackler.  The new millennium was less kind, however, as Scott lost her
policeman fiance in the World Trade Center on 9/11 and died in her sleep at the age of 52 in 2005.
 
 
 
 

Then:

John Travolta's older sister (by 14 years) was already a working
actress when she landed the gig as Horshack's mom, but it probably didn't hurt to have Vinnie Barbarino in her corner. That's what next-big-thing baby brothers are for!
 
 
 

ABC/Retna

TV motherhood seemed to come naturally to Ellen. Not only did she somehow cope with problem child Arnold Horshack, she also played Scott Baio's mom on 'Happy Days,' 'Joanie Loves Chachi' AND 'Charles in Charge.' Perhaps waiting for Baio's big comeback, she currently lives in Idaho
with her actor-husband Jack Bannon.
 
 
 
 

Then: Carvelli got knocked out by Horshack in the ring AND got ratted out for planning a gang rumble in the 'Sweatside Story' ep. But then he convinced the gullible Sweathogs he had met aliens in 'Class Encounters
of the Carvelli Kind.'

Now: Fleischer is best known as the title character in 'Who Framed Roger Rabbit.' In addition to voice work in animated flicks like 'Polar Express,' he's a standup comedian and character actor.
 

Jeffrey Mayer, Wirelmage.com

Then: A fourth-season substitute when Kaplan went AWOL from the series, Della did what subs often do: make the best of a bad situation.

Now: Reese started out a gospel singer touring with Mahalia Jackson, then became a successful pop and jazz vocalist, TV talk show host, as well as having recurring roles on shows like 'Sanford & Son' before her success on 'Touched by an Angel.' She lives in L.A. with her husband, Franklin Lett.