When Krusty the Clown is announced as the recipient of the Nobel Peace Prize, Homer invites Bart to accompany him on a trip to Oslo for the ceremony. Sensing that Lisa would feel left out, Marge surprises her with a week-long retreat at performing arts camp, where she where she is greeted by her artsy counselors and fellow musically inclined campers, who inspire her to embrace her creative side. After she returns to Springfield, Lisa becomes restless with her ho-hum suburban lifestyle and sneaks off to Sprooklyn in hopes of connecting with her inner hipster, but she soon realizes that the city is not the same as camp .
When Grampa gives each member of the family a portion of his savings, Lisa and Marge spend their money in drastically different ways. Lisa invests in Nelson's brand-new business venture, but soon realizes that her friend's instant success might lure him away from the classroom. Worried that his judgment might be clouded, Lisa introduces Nelson to the well-educated and successful creator of Facebook, Mark Zuckerberg, only to find out that he too dropped out of school. But when the soaring business suddenly takes a sharp turn, Lisa teaches her friend that education is invaluable.
Visit by a Springfield Elementary alum-turned-Ivy-League student pushes Lisa to question her own go-getter attitude and reevaluate the scope of her extracurricular activities. Convinced that there is no such thing as having too many clubs or activities listed on her resume, Lisa jumps at the opportunity to coach Bart's little league team. Despite having little understanding of baseball, Lisa coaches the team to a record winning streak by putting her book smarts in statistics and probability into play. But when Bart questions Lisa's coaching tactics and confronts her for taking the fun out of baseball, Lisa benches him from the championship game. Hoping to lift his spirits, Marge spends the day with Bart at an amusement park where MLB manager and former catcher Mike Scioscia gives Bart sound advice and reminds him of his genuine love of the sport. Meanwhile, with one last chance to win the game, Lisa makes an unexpected call and learns that there is more to sports than winning.
Beware of ouija boards, vampires and unexpected guests in the 21st annual installment of the "Treehouse of Horror." In "War and Pieces," the first of three spine-tingling tales, Marge, worried about the effects of excessively violent video games, encourages Bart and Milhouse to give wholesome, classic board games a shot. The best friends discover that board games aren't boring after all when they find themselves playing a real-life game in which they must beat all the challenges before they are allowed to return to home. The supernatural spells continue in "Tweenlight," when Lisa becomes smitten with a mysterious new student, Edmund, who also happens to be a vampire. When a romance blossoms, the young lovers run away to Dracula-la Land, leaving Homer to come to Lisa's rescue. In the final frightening fable, "Master and Cadaver," Homer and Marge set sail on a romantic second honeymoon, but are interrupted when they rescue Roger, a castaway who escaped an attempted poisoning on his ship. Convinced that Roger is sabotaging their getaway and plotting a murder of his own, Homer and Marge take matters into their own hands.
When the Simpsons visit Marge's childhood home and discover a box of her old belongings, Lisa is surprised to learn that Marge was once a stellar A+ student. After discovering that a distraction caused Marge's grades to slip in high school, Lisa fears that she will end up just like her mom unless she pledges to focus solely on academics. When Lisa learns that prep school Cloisters Academy is accepting new students, Marge puts her feelings aside and makes a secret deal allowing Lisa to attend her dream school. Meanwhile, Bart puts Nelson and his bully ways in place and unintentionally claims the title of School Bully, and Lisa learns a lesson in family and altruism.
After learning that he is suffering from multiple illnesses and has only a few weeks to live, Mr. Burns becomes distraught by the town's less-than-sensitive reaction to his announcement. Following an unexpected turn of events, Bart finds Mr. Burns weak and vulnerable in the wilderness and secretly takes him into the Simpsons' home. But when Homer and Marge learn about their new houseguest, they decide it's payback time, and Lisa, determined to stand up for Mr. Burns, learns that old habits die hard.
When a pigeon flies through the Simpsons' home and suffers a broken wing, Bart makes it his duty to care for the bird - whom he names Ray - and nurse it back to health. When Ray is ready to fly, Homer decides to enter him in a bird race when Danica Patrick appears to him in a dream. Things don't go according to plan, however, when Santa's Little Helper swallows Ray. Worried that Bart needs some help getting over the loss, Marge and Homer take him to a therapy session with Dr. Thurston, who advises that the only cure for Bart's blues is to give away the family dog. But when the Simpsons visit the pup's new home, a shock causes them to rethink their decision.
It's beginning to look a lot like Christmas in Springfield, but while Marge gets in the holiday spirit, it's bah humbug for the rest of the family. Disappointed that she is alone spreading the holiday cheer, Marge sends a letter to Martha Clause to help her save the family Christmas. Martha comes to the rescue and transforms the house into the North Pole chalet Marge has always dreamed of, but when the family is noticeably absent from the perfectly trimmed holiday home, she realizes that it's Homer and the kids who make the holidays special. Meanwhile, the Simpsons get ready to sneak away for a tropical holiday vacation in Hawaii, but surprise visitors Mr. Burns and Moe's new friend, Katy Perry delay their getaway. Four special holiday tales will be spun.
Homer spends New Year's Eve in the Springfield Penitentiary after getting caught bribing an official. An FBI investigator offers to reduce his jail time if Homer agrees to go undercover as an informant to investigate Fat Tony. When Homer forges a special bond with Fat Tony and his family, he becomes conflicted between his obligation to the government and his loyalty to his new family. After an unexpected turn of events, Fat Tony's cousin Fit Tony seeks to settle a score with Homer, but winds up teaching him an important lesson.
After the fourth graders and fifth graders engage in a heated dodgeball battle, Bart discovers that one of the fifth graders has the same mysterious scar on his hand. Puzzled by the matching blemishes, Bart tries to understand why and how he got it, leading Marge to explain that seven years ago, she and her girlfriends formed the "The Cool Moms," a tight-knit group of moms who set playdates for their young boys. Inspired to reconnect with the women, Marge's social life soon becomes recharged, but when Bart's playdates stop being fun, he attempts to break up the club, and Marge finally remembers why she left the group in the first place.
When Smithers offers to help transform Moe's dingy pub into a more refined and trendy lounge, the revamped "Mo's" quickly becomes Springfield's local gay hangout. With Smithers' friends and colleagues infusing new life into "Mo's," business starts to boom, but Moe inadvertently leads his new bar patrons to believe that he, too, is gay. Afraid that telling the truth would hurt his newly flourishing business, Moe's new friends teach him a lesson in acceptance. Meanwhile, Principal Skinner becomes smitten with the new free-spirited music teacher, Ms. Juniper, who inspires the by-the-book principal to take chances. When Skinner finds out that Ms. Juniper's daughter, Melody, has a crush on Bart, he uses Bart to get close to Ms. Juniper.
Homer becomes obsessed with "Thicker than Waters," a 1980s family sitcom written by David Mamet, and models his parenting skills after the show's sensible father much to the chagrin on Bart, who desperately sets his sights on a brand new dirt bike. But when Homer insists that Bart must earn the dirt bike, Bart takes matters into his own hands and schemes with Russian and Chinese spies to provide top-secret information in exchange for the new bike, which winds up putting Bart in a precarious situation. Later, James Lipton conducts an interview with a television cast on "Inside the Actor's Studio".
After spending another Valentine's Day alone, Moe attends a seminar led by Dr. Kissingher in the hopes of gaining more confidence with women. Moe takes the doctor's advice and asks Homer to be his wingman, but Moe becomes distraught when women are drawn to Homer as well. Meanwhile, Marge discovers her first gray hairs and surprises both her family and the neighborhood by going completely gray and sporting a brand new mature do, but Bart is not humored when the neighborhood kids tease him about Marge's look. Later, Marge confronts Homer when she learns that he is becoming increasingly popular with the young ladies, but Homer helps Marge realize that he only has eyes for her and proves that love is still in the Springfield air.
Bart's cartoon about an angry dad is turned into "Angry Dad: The Movie" and quickly becomes a critics' favorite. When Russell Brand presents the Golden Globe to Bart's film, Homer usurps the podium and gives his own acceptance speech. The film's winning streak continues with Homer taking credit at each ceremony, so when "Angry Dad" receives an Oscar nomination, Bart keeps it a secret. With the help of DJ Kwanzaa, Homer and Marge arrive at the ceremony just as Halle Berry presents the award. Bart's fellow nominee, Nick Park, helps him realize that creating a film is a team effort, and Bart gives credit where credit is due.
After a field trip to the desert, Lisa discovers that the desert water mysteriously makes typically combative creatures get along, so she brings some of the water home as a souvenir. When Grampa moves in with the family after getting kicked out of the retirement home, Homer secretly tests the desert water on Grampa, who is instantly cured of his crankiness. A pharmaceutical representative gets word of Homer's discovery and quickly tries to replicate the water into a drug, using Grampa as the primary guinea pig. But when the pills get in the wrong hands and are sold on the black market, unexpected side effects of the new drug take an eye-popping toll on the elderly citizens of Springfield, and the Simpsons learn that their new medical cure comes with major consequences.
The town is abuzz when Cheech and Chong announce a Springfield stop on their much-anticipated reunion tour. But when Cheech and Chong take the stage in front of their loyal fans, the jokes were just not the same for Chong, so Homer steps in and delivers all the punchlines by heart. Impressed, Cheech invites Homer to go on tour with him as new duo "Cheech and Chunk" while Chong forms a more progressive comedic team, "Teach and Chong," with Principal Skinner. While Homer is on tour, Marge attempts to help the neighborhood cat lady and change her hoarder ways, but turns into a hoarder herself in the process, and Homer realizes that life on the road is not all high times and slapstick humor.
When Homer inadvertently humiliates Bart in front of a stadium crowd, Marge encourages Homer to enroll in a fathering enrichment class taught by therapist Dr. Zander. Shocked to learn that Homer often strangles Bart for mischievous behavior, Dr. Zander conducts a series of treatments with the help of Kareem Abdul-Jabbar to teach Homer what it feels like to be young and small. But when Bart learns that the therapy sessions have transformed Homer into a pushover, he takes advantage of Homer and becomes a school bully. Hoping therapy could also cure Bart of his bullying habits, Marge enlists Dr. Zander's help to patch their relationship.
The family is greeted by folk singer Ewell Freestone when they visit a peach farm, but when Marge goes overboard with peach-inspired dishes, Lisa and Bart try to get rid of the unwanted fruit. Later, Lisa becomes a magician's apprentice to the legendary Great Raymondo who helps her develop her craft, but a schoolgirl crush clouds her judgment when she is coaxed into revealing the Great Raymondo's most famous magic trick to his phony archnemesis. But when the rival magician's act takes a risky turn, the Great Raymondo has one last trick up his sleeve and stages showdown with Ricky Jay, Penn & Teller and David Copperfield, showing them why he is the master of the craft.
Fat Tony and Selma, Marge's painfully blunt sister, fall in love and get married after a whirlwind courtship. Marge has her reservations about the couple's marriage after Selma begins to prioritize her looks and ritzy new lifestyle over her family, so Fat Tony invites Homer and Marge to a weekend getaway at the Jersey Shore. Meanwhile, Bart discovers a special talent that allows him to detect the location of truffles by smell, and Lisa jumps at the chance to capitalize on the rare culinary treasures.
After Homer discovers a genius talent for styling hair and opens his own salon, he becomes Springfield's most in-demand hair stylist. But having to listen to women's problems and gossip all day long leads Homer to believe his gift may actually be a curse. Meanwhile, when Milhouse decides to live each day to the fullest, he comes out of his shell and professes his love for Lisa, only to have his heart broken. Milhouse then catches the eye of popular fifth-grader Taffy, causing Lisa to make a bold move.
When the Simpsons discover a collection of keys to every door in Springfield, Lisa stumbles upon an eerie hidden classroom beneath Springfield Elementary School. When she shares her discovery with Principal Skinner, the secret room mysteriously disappears and he takes the only key away. A determined Lisa uses her detective skills to lead her back to the room to solve an old school mystery.
Feeling guilty for getting Mrs. Krabappel suspended after one of his school pranks, Bart helps her escape detention, and Ned Flanders winds up saving her life in the process. When Edna and Ned start dating, he is surprised to learn she's been with many of Springfield's men, including Homer and Aerosmith drummer Joey Kramer .