15.01: "Cereal Killer"

In the landmark three-hundredth episode, Homer accidentally swallows a dangerous item in his breakfast cereal and he is taken to hospital. Marge suggests that he takes the cereal company to court. However, things get out of hand when he defends himself.

15.02: "Death of a Saleswoman"

A saleswoman turns up at Marge and Homer's apartment, and they can't seem to get her to leave. However, when her dead body is found the next day, the two panic and are not sure what to do, and so they decide to enlist the help of Lenny, Carl and Barney.

15.03: "How I Learned to Stop Worrying and Love Beer"

Homer decides to teach Marge how to become more relaxed in her life. However, his teaching ways get out of hand and she ends up becoming extremely drunk, possibly threatening him, their friends, and everybody around them. Homer must sober her up.

15.04: "Flood in and Flood Out"

A flood is threatening Springfield, and everybody is temporarily re-located to a shelter underground. However, things get out of hand in the shelter and Homer, out of all, is the most fed up. Meanwhile, Carl manages to find love in the underground shelter.

15.05: "Marge the Overachiever"

Marge realises that she is an overachiever, and so she decides to give up being one and become a person like Homer. However, Homer is beginning to get fed up because she has changed her feminine ways into a much more masculine personality.

15.06: "Gay Arnold!"

Valentine's day has arrived and Homer finally meets his secret admirer, a guy called Arnold. (11.15 "Valentine's Gay and 13.09 "Seeing Straight"). However, he begins to panic when he starts to become good friends with him, Marge attempts to prove he will be fine.

15.07: "Lenny vs. Himself"

Lenny has become extremely depressed over his break-up with Jill, and so he becomes determined to change himself and live a fresh, new life. However, his friends don't want him to leave, and so they attempt to show him that he should remain in Springfield.

15.08: "XXX-Men"

Homer, strapped for cash, decides to get a job working for a video pornography store. However, Marge is disappointed that he couldn't find a better job. Homer, meanwhile, is beginning to get worried when he realises that everybody is now calling him a pervert.

15.09: "Dude, Where's My Ma?"

Homer realises that Marge's mother has unexpectantly vanished and this makes him think of his own mother. With Mother's Day coming up, he becomes determined to find out more about her. However, he realises just how difficult it is to get anything out of Abe.

15.10: "Beauty and the Priest"

Homer has turned to religion once again after he realises that he and Marge may be evicted from their apartment. However, he later realises that the current priest has quit, and so he decides to take up the position himself. Marge tries to get him to re-consider.

15.11: "Guess Who's Crack?"

Amy turns up at the apartment, explaining that ever since she graduated from Springfield College, she has been homeless. Marge offers her a place to stay. Homer thinks that something strange is going on, and when he is offered crack by Amy, he panics.

15.12: "Me & Swim"

Whilst taking a canoe trip, Barney discovers that he can't swim, and Homer is worried that he might ruin the entire trip because of this. Meanwhile, on the second canoe, Marge is worried when she and Lenny encounter an extremely dangerous crocodile.

15.13: "The Sung and the Restless"

Marge is noticed for her singing talent, and she is offered a record deal. However, when she realises that the whole thing was a scam to get her money, she attempts to track down the supposed music producer, with the help of Homer, and sort everything out.

15.14: "Looking for Homer in All the Wrong Places"

Marge returns from a short weekend break with Homer, and announces that he has unexpectantly gone missing. With the help of Lenny, Carl and Barney, they go back to the resort to find him. Meanwhile, Homer, stuck in an elevator, is trying everything to get out.

15.15: "The Fools of the Game"

It is April Fool's day and everybody is trying to pull off their best pranks. However, a prank done by Homer goes too far and he is ridden with guilt after he accidentally deafens someone. He becomes determined to make it up to this person in any way he can.

15.16: "From Shelbyville, With Love"

Lenny's ex-girlfriend, who moved to Shelbyville a while back, has returned and the two start another relationship. However, he hasn't explained that he has been married twice before. Meanwhile, Homer decides to rent a porno, but he realises that he must hide it from Marge.

15.17: "The Virgin Margie"

Homer is shocked to discover that Marge, did, in fact, have sex with other guys before she met him and he is offended that she lied about this. Marge becomes determined to make it up to him. Meanwhile, Lenny's relationship with his ex-girlfriend Rachel is developing.

15.18: "Car Frontier"

Marge convinces Homer to purchase a new car as the old one is falling to pieces. However, she is angry when she realises that he has bought a very expensive van, and it can't be returned or exchanged. She tells Homer to find a good use for the van, but it is hard.

15.19: "The Heart of War"

When Homer suffers a minor heart attack and is taken to the Springfield hospital, Marge decides to help him become a healthier person, and he agrees. However, she is greatly offended when she realises that he has been smuggling fatty foods behind her back.

15.20: "Paint Misbehavin'"

Marge and Homer decide to start re-decorating their apartment. However, things get out of hand, and Homer ends up spraying the entire main room with a disgusting color. With the help of Barney, Lenny and Carl, they attempt to get everything back to normal, but it is hard.

15.21: "The Return of Jill Marsh"

Jill, Lenny's ex-wife, returns to Springfield and she confronts Rachel about her relationship with him. Rachel is shocked when she realises the truth, and she decides to break up with Lenny. Jill, meanwhile, wants to get back together and Lenny must make a tough decision.

15.22: "The Class is Always Greener"

Marge and Jill decide to enroll in a environment club at the Springfield activity center. However, she later realises that nobody actually takes it seriously and all they want to do is gossip. With the help of Jill, Marge decides to completely change the entire club for good.