The couch gag features Thanos from the Marvel Cinematic Universe, disintegrating the Simpsons family except for Maggie. This is a reference to the ending of the film Avengers: Infinity War.
The episode's name is a reference to the novel The Girl on The Bus, written by Nick Holland and/or the psychological thriller The Girl on The Bus by N.M. Brown.
The song Lisa sang on the bus is a parody of the song "Belle" from Disney's Beauty and the Beast.
The U.S. Ninja Ultimate Beast Blaster is a parody of SASUKE (known as Ninja Warrior in most of the countries outside Japan) and its American counterpart, American Ninja Warrior, and Netflix's Ultimate Beastmaster. Both shows also share the same obstacle courses' designer (the ATS Team).
Marge and Lisa reenact the scene where Sideshow Bob appear in front of Bart and Bart shouts "AH! Sideshow Bob!", with Marge appearing out of the shadows saying "Hello, Lisa" and Lisa shouting "AH! Sideshow Mom!".
Sam's father drives a Toyota Prius.
When Ned tries to act like Homer, he says the words "Annoyed Grunt" instead of "D'oh!", which is what an annoyed grunt is.
Bart‘s prank on Homer by unscrewing the salt shaker is the same prank he did on Milhouse in Homer Defined.