Who were the sweathog extras in welcome back kotter?

In "Welcome Back, Kotter," the "Sweathogs" were a group of high school students in a remedial class at James Buchanan High School. The main characters included Gabe Kotter, played by Gabe Kaplan, and his students, who were portrayed by actors such as Ron Palillo (Arnold Horshack), Lawrence Hilton-Jacobs (Freddie "Boom Boom" Washington), and Robert Hegyes (Juan Epstein). The term "Sweathogs" referred to their rough, rebellious demeanor and the struggles they faced in school. The show humorously depicted their interactions with Kotter, who was a former "Sweathog" himself.