Jennifer Aniston appeared in South Park

In 1996, Jennifer Aniston appeared in South Park as Mrs. Stevens Choir Teacher (Voice, Guest stars) in "Rainforest Schmainforest" (Season 3, Episode 1).

South Park is an American animated sitcom, created by Trey Parker and Matt Stone for the cable channel Comedy Central. Intended for mature audiences, the show has become infamous for its crude, surreal, satirical, and dark humor that lampoons a wide range of topics. The ongoing narrative revolves around four children—Stan Marsh, Kyle Broflovski, Eric Cartman, and Kenny McCormick—and their bizarre adventures in and around the titular Colorado town.

Jennifer Aniston, Richard Belzer, Natasha Henstridge (billed in the opening credits as "The chick from Species"), Norman Lear, and Peter Serafinowicz have guest starred as other speaking characters. During South Park's earliest seasons, several high-profile celebrities inquired about guest-starring on the show. As a joke, Parker and Stone responded by offering low-profile, non-speaking roles, most of which were accepted; George Clooney provided the barks for Stan's dog Sparky in the season one (1997) episode "Big Gay Al's Big Gay Boat Ride", Leno provided the meows for Cartman's cat in the season one finale "Cartman's Mom Is a Dirty Slut", and Henry Winkler voiced the various growls and grunts of a kid-eating monster in the season two (1998) episode "City on the Edge of Forever". Jerry Seinfeld offered to lend his voice for the Thanksgiving episode "Starvin' Marvin", but declined to appear when he was only offered a role as "Turkey #2".