Bart's fourth grade class is merged with another fourth grade class when teacher Mrs. Krabappel is absent. In the crowded classroom, Bart is forced to sit by a new student named Nikki. At first they dislike each other, until Nikki admires Bart's artistic skills. Bart seeks romance advice from Homer, who passes him off to Grandpa Abe. After Grandpa advises Bart to kiss Nikki, however, when Bart does so after the two skateboard together, she recoils in disgust. Nikki's attorney parents threaten to sue the school unless it is declared an "affection-free environment". Superintendent Chalmers causes a play in which Willie plays Nikki and Skinner plays Bart, meaning they are forced to kiss. Bart is confused at the outcome of this seemingly innocent action, and his confusion is later amplified when Nikki hides in his locker and kisses him again.
Meanwhile, Lisa becomes more popular when she receives an F on a test, but becomes unpopular again when it is revealed that her test was mistakingly given to Ralph and really got an A+++, both tests were mixed up as the F grade was supposed to be given to Ralph who had written Lisa's name on his test. She blogs about being ostracized as an overachiever, and her post is noted by a mysterious blogger known as Flotus 1 who turns out to be First Lady Michelle Obama. Obama drops by Springfield Elementary to give a speech about the importance of academics and recommends that the students should be nice to Lisa and other overachievers, including Martin Prince and Allison Taylor.
Bart and Nikki have been watching this speech from the roof, and Bart confesses to Nikki he does not understand her ever-changing moods. They argue and Bart stumbles, falling off the roof. Nikki says "I love you," but seeing that Bart is breathing treats him badly again. Bart stops breathing again, but the school's "no touch" policy prevents anyone from performing CPR. Nikki defies the policy and revives Bart via mouth-to-mouth, thus setting off a montage of kiss scenes from various movies, some of which (such as Alien3) never even had kiss scenes in them. When Bart awakes, Nikki's mood changes yet again and Bart remains in a state of complete confusion over female behavior. He tells her he does not care what happens between her and him, but then changes his mind and yells out "I love you!" after she kisses him once again.
Throughout the episode, Nelson Muntz has befriended a blind boy and teaches him how to laugh at the misfortunes of others. At the end, the blind boy tricks Nelson into believing that a punch he sustained after insulting Nelson restored his sight. When he reveals to Nelson that this was a prank and laughs Nelson's signature "haw haw", Nelson is as impressed as he is touched by the achievement.