Ron Palillo, best known as mouthy classroom goofball Arnold Horshack on the 1970s TV series Welcome Back, Kotter, has died, according to Greg Hauptner, founder and CEO of a Florida charter school where the actor taught classes in 2009.

Palillo was 63. Details of his death have not been released.

Before being hired by G-Star Academy in Palm Springs, Fla., in 2009, Palillo had lectured in colleges and high schools all over the country for years.

“From the moment I heard about G-Star seven, eight years ago, it sounded like everything I wanted as a student when I went to high school,” Palillo said in 2009.

“To have this when I was a kid would’ve been astonishing and I knew I wanted to be part of it.”

Palillo is a University of Connecticut graduate who taught entry-level acting at G-Star.

Palillo played Horshack on the popular show Welcome Back Kotter that also starred a young John Travolta.

Palillo was active in local theater in Palm Beach County, Fla., where he directed and acted in A Closer Walk with Patsy Cline and The Phantom of the Opera.

“I’ve always felt very at home here,” Palillo said in 2009. “People go out of their way for you in West Palm Beach. They don’t do that in New York.”