"Timber!" Brooke bonds with her long-lost mother, much to her dad's objection as it causes tension between him and Jane. Meanwhile, Lily and Sugar try to save the forever tree from being cut down. While Sam tries to fix the mess she caused that results in a startling revelation.
"Baby Don't Do It" Ms. Glass equip her students with electronic baby dolls that require maternal care in an attempt to teach them about "the burden of parenting." Meanwhile Sam tries to convince Brooke not to leave, pulling out every trick at her disposal to do so.
Carmen goes to see Sam in the motel she and her mother are staying in, early in the morning, her house being a war zone. She brings in a "few" things, some of it being Sam's stuff including a jacket she is wearing. As Sam goes through the bag of stuff Carmen finds a bruise on her shoulder, deciding to keep the jacket on. Meanwhile, Jane discovers she is pregnant, freaking out until she see's her "lima been's" heart beat. Brooke tries to talk her dad into calling Jane, who tells her they agreed to take two weeks off to figure things out. Brooke decides to call Jane, ...
"Joe Loves Mary Cherry" Nicole decides to get some revenge on Mary Cherry, using Harrison to do it. While she and Mary Cherry try to persuade Brooke to dump Josh and start dating George, in hopes that the new coupling will save's Brooke's plummeting popularity, and thus save their own as well.
"Style and Substance Abuse" Brooke withdraws from the homecoming queen race, whose nominees include a shocked Sam, Carmen, Mary and Nicole. Brooke instead joins the race for student council president. The death of a student leads to mandatory drug testing.
"Ur-ine Trouble" Principal Krupps announces plans for a random drug test of the student body after one of Kennedy's best and brightest test positive for drugs, instituting a unique punishment. Sam decides to drop out of the race for homecoming queen, not liking what it is turning her into. Nothing prepares them for what happens during the student council debates when Harrison reveals something shocking about himself.
"Misery Loathes Company" Mary Cherry recruits Sam to ghostwrite her memoirs after learning that her mother has plans for a book that paints the younger Cherry in a bad light. Brooke deals with her own demons after the events of the Student Council race landing her back into old habits.
"Are You There God? It's Me, Ann-Margret" Harrison encounters God in a hospital storage room who knows personal things about him. Carmen attends a meeting for teens with alcoholic parents with an unexpected member. The school puts on the play Eqqus, with Josh and Lily as the leads.
Harrison's roommate Clarence passes away sending Harrison into a depression that leads to a suicide attempt and a glimpse of what life would have been like if he had never been born, by his guardian angel.
"Fire in the Hole" Harrison returns to school, Sugar and Harrison planning him a welcome back surprise. Ms. Glass tells her students that they must perform in a play she has written about sexually transmitted diseases. While Sam tries to have her first time with George.
"The Shocking Possession of Harrison John" Harrison decides to change his image by asserting himself, but Mary Cherry worries her "Joe" is acting too much like Nicole. Sugar and Josh hit a rift in their friendship while Nicole discovers a shocking secret about her past.
Mary Cherry is forced to wear "hobo sheik" clothing and hunt for food in a dumpster after her mother has financial troubles having her wardrobe seized. While Sam and Carmen have the challenge of saving their yearbook.
Upon car pooling to school (after Mary crashed her car on the way to Glamazon practice) Lilly, Sam, Brooke, Carmen and Mary Cherry talk about not having any regrets they come upon a car accident involving whom they believe to be April Tuna. Sam says she does have one regret, not being able to say goodbye to April Tuna. News of her passing quickly spreads through the school, the facts getting a bit stretched, as well as Josh's mullet. Mary Cherry and Bobbi Glass scheme to get a day off from school on Friday in their grief. Unfortunately Krupps decides to call in a ...
After another food fight at school, Brooke and Carmen decide they are so over high school and high school boys. During breakfast Nicole asks her mother to take a look at her college essay on what it is like to be adopted, revealing to her mother that she has found her birth mother wanting the two to meet. Nicole's mother refuses to meet or hear her name ever again. Sam is feeling guilty that she has hurt Harrison, George try to sway her fears about him not wanting to talk to her again, giving her a kiss that Harrison sees, and Sam notices Harrison walking by. During a...
In one of the most powerful episodes; homophobic behavior by members of her science class leads Lilly to launch a gay and lesbian support group at school, but her efforts create tension among her friends especially with Josh. A new student spray paints "Fag" across Lilly's locker in an attempt to hide his own feelings. Harrison is the first and only one of her friends to join her club after Josh drops out from an alteration in the boys locker room. Sugar Daddy joins the club after what happens in the locker room, having his own problems with discrimination because of ...
Nicole sets out to prove that her power is not based on her "twin set" her plan involves April, Brooke and taking down everyone who gets in her way. Meanwhile Brooke butts heads with her dad about the college guy she is dating.
After being humiliated when she tries out for "Pop Tarts" Mary Cherry decides to assemble a team to compete on a local cable academic-challenge program in hopes that she'll be discovered for her looks and "personality". Cherry Cherry has to attend Kennedy High after her low SAT score comes back to haunt her. She wants in on her daughter's team when Josh also tries out for it. Josh turns to Harrison to help him get onto Mary Cherry's team to prove he isn't just another dumb jock. Harrison discovers that Josh has an uncanny knowledge of chicken that gets him on Mary ...
When Ms. Glass asks the glass to write down where they went on spring break and how many people they slept with, the Kennedy High students are quarantined at the school after Harrison shows symptoms of an exotic disease, Rip Valley Fever, he may have contracted during his vacation in Yemen. He and Sam are locked up in the nurses station together forcing them to face their feelings for each other. In a hilarious "I Know What You Did Last Summer" spoof, the kids are hunted by a mysterious killer who knows what each of them did. Mary Cherry is the first to get the call ...
Sam and Brooke give Harrison the silent treatment after they realize that he misled both of them, meanwhile having to decide on a name for the new baby. Josh learns that his mother's new job requires them to move to another state away from school, his friends and Lily. Mary Cherry backs into Big Bertha Muffin's car while impatiently waiting to park her Hummer, Carmen tells her that she has to leave a note, and in typical Mary Cherry fashion she signs it Nicole Julian. In chemistry class Ms Glass decides to teach the class a lesson on trust. Brooke convinces Sam she ...
In the series finale cliffhanger, Sam's mother gives birth to a new baby girl. With the junior prom coming it seems no one has a date, with Lily and Josh more concerned about their new marriage situation, George and Sam split up Nicole also going stag. Ms. Glass posts a tenant flyer that Josh and Lily consider taking, Josh being frustrated with living with Lily's mother who won't let him sleep with his own wife. Brooke and Sam are both at odds when it comes to deciding who will go to the prom with Harrison so Brooke suggests that he take both of them to the prom ...