Bart Gets a 'Z'

"Bart Gets a 'Z'" is the second episode of The Simpsons' twenty-first season. It originally aired on the Fox network in the United States on October 4, 2009.

In the episode, the fourth grade students of Springfield Elementary School decide to spike Ms. Krabappel's coffee in order to teach her a lesson after she takes away their cell phones. She is fired by Principal Skinner, who hires a new teacher named Zachary Vaughn. Although Vaughn is a hip young teacher who impresses the students, Bart is plagued by guilt and tries to get Ms. Krabappel hired back.

In its original airing, the episode had an estimated 9.32 million viewers and received a Nielsen rating of 5.1/8. The episode was written by Matt Selman, and directed by Mark Kirkland.

Mrs. Krabappel's positive attitude is crushed when she sees her students distracted from class by their cell phones, so she takes the devices away and puts them in the drawer with the biology frogs. This angers Bart and the other children, and they decide Mrs. Krabappel needs to "chill out". Bart understands that Homer is goofy and easy-going once he has had a few beers, so the students decide to spike Mrs. Krabappel's coffee with liquor they steal from their parents. The next day, once she has consumed a mug of heavily-spiked coffee (with sly encouragement from the kids), Mrs. Krabappel becomes very intoxicated. She sings a loud, off-key, incoherent version of "This Old Man" with her students, and ends up hitting on Dewey Largo and disrupting an assembly bidding farewell to foreign exchange students. Principal Skinner is forced to fire her, although reluctantly, even giving her his hankey when she starts crying.