A Tale of Two Springfields/Gags

Couch gag

 * Bart arrives at the couch first and places a whoopee cushion under Homer's spot. When the family sits down, Homer sits on the part of the couch with the whoopee cushion underneath and triggers its farting sound. Homer grins sheepishly at Marge, Lisa, and Maggie (who are frowning) while Bart laughs.