Nate from You Look Different in Real Life has the Grease soundtrack on his phone. When Justine expresses surprise, he says, "I'm a T-Bird at heart," and reminisces about Felix getting him into the movie.
In The Mermaid's Mirror, Kai auditions for the role of Danny in his school's production of Grease. He tries to talk Lena into auditioning for Sandy. He gets cast as Kenickie instead.
Glee had a plotline involving a production of Grease at McKinley High. The previous season also featured a Shot-for-Shot Remake of "Summer Nights" as featured in the movie.
The Goodies episode "Saturday Night Grease" not only references it in the title, but has a parody of Grease Lighting" called "Grease Cycling", and a cover of "You're the One That I Want" performed by Graeme Garden, who's dressed like Sandy at the end of the movie.
ThisCollegeHumor sketch features the Burger Palace Boys reacting appropriately to the rather unfortunate implications of Kenicikie's line "did she put up a fight," with the reveal that Kenickie is a rapist, causing the other boys to beat him up in anger.
Bob's Burgers: In "Something Old, Something New, Something Bob Caters For You", the Belcher kids make a bet over who gets to be in the most photos during a wedding Bob is catering, and the loser has to clean the grease trap at the restaurant. Gene tells Tina and Louise "Better call yourselves Sandy and Rizzo, 'cause you're about to be in grease!"
In the Family Guy episode "Let's Go To The Hop" "Give Up The Toad" is a parody of "You're The One That I Want"
In "And I'm Joyce Kinney" a cutaway gag shows the original ending where Danny and Sandy are trapped in the sky with no way to get down.
CollegeHumor sketch features the Burger Palace Boys reacting appropriately to the rather unfortunate implications of Kenicikie's line "did she put up a fight," with the reveal that Kenickie is a rapist, causing the other boys to beat him up in anger.