Pranks and Greens  "Pranks and Greens" is the sixth episode of the twenty first season of "The Simpsons". It originally aired on the Fox network in the United States on November 22, 2009. In this episode, Bart tracks down an immature, college-aged man named Andy Hamilton who was once hailed Springfield Elementary's best prankster and encourages him to do something with his life. The episode was written by Jeff Westbrook and directed by Chuck Sheetz. It was watched by approximately 7.03 million viewers during its original airing. After Bart is apprehended for playing pranks on the teachers of Springfield Elementary, Principal Skinner reveals to Bart that he is not the greatest prankster to ever walk the halls of the school. Bart is shocked by this revelation and sets out to discover the identity of this prankster. After sifting through countless back issues of the school paper, he discovers that there is a two-week gap in its publication dating back 10 years, and that there is a substantial change in Principal Skinner's demeanor and appearance before and after the gap. Groundskeeper Willie eventually tells Bart that he was once the school swim instructor, and that Principal Skinner was once fun-loving and laid-back until an incident dubbed "Night of the Wigglers". Here, a prankster named Andy Hamilton locked Skinner in a pool full of earthworms for three days, changing Skinner's personality for the worse. Meanwhile, Marge is harshly criticized by other Springfield mothers for serving unhealthy snacks at their "Midday Mommies" meeting. In response, she burns the family's junk food and the family purchases organic food, which is very expensive and has a short shelf life. At the next meeting, Marge meets with more criticism when she uses non-stick bakeware (which contains PFOAs) and plastic drinking bottles marked with number 7 (which has the potential to leak BPA). The other mothers storm away and Marge realizes that she misses eating junk food. Homer catches Marge eating from his stash of candy, and the two of them indulge in junk food together and apparently make love, and Homer points out that, ironically, the junk food is healthier than organic food. They then agree to only make the kids eat healthy. Bart meets Andy Hamilton and discovers that he is unemployed and lives with his mother. When Lisa suggests Andy is a loser, Bart gets him a job as Krusty the Clown's assistant as a favour Krusty owes him, but is angry when Andy quits after one day. Bart gets him rehired and goes to check Andy's progress.