"Hello, I'm Jerri Blank and I'm a 46-year-old high school freshman. For 32 years I was a teenage runaway. I was a boozer, a user, and a loser. My friends were dealers, cons, and 18 karat pimps. But now I'm out of jail, picking up my life exactly where I left off. I'm back in high school, living at home, and discovering all sorts of things about my body. I'm finding out that though the faces have changed, the hassles are just the same."
After deflowering a male classmate, Jerri finds out that she has contracted a series of STDs (syphillis infested with crabs which are carrying gonorrhea) and must inform all her partners of her discovery. Meanwhile, Mr. Jellineck and Mr. Noblet have problems concealing their own bout with a particularly noticeable STD.
Told in her art class to photograph something that represents freedom, Jerri creates a nude self-portrait which is immediately banned by the principal. So Jerri goes on a hunger strike.
When Jerri discovers her American Indian heritage, she attends a camp run by a councilor who teaches adopted Indian children about aspects of their culture, such as alcoholism and gambling.
Jerri and class hunk Laird are having a fling, but he is insistent on keeping it a secret. So Jerri finds herself forced to hide out in odd places like Laird's locker, the trunk of his car, a trash can, etc., so they can continue their secret rendezvous. Meanwhile, Jerri's stepmother experiences relationship troubles with Stew, prompting an unusual bonding moment between stepmother and stepdaughter.
Jerri's new daddy Stew starts to act very strangely, which makes Jerri reluctant to bring him to class for Occupation Week.
Jerri joins the track team, but years of hard living have taken their toll on her physique. She turns to supplements of a most dubious nature to improve her performance, and the results surprise everyone at Flatpoint.
At the bequest of Mr. Noblet, Jerri takes over an advice column formerly penned by Mr. Jellineck, which results in diabolical intentions on Geoffrey's part towards Chuck, and anger from nearly everyone in Flatpoint High towards Jerri.
Jerri is asked out at a school wrestling game, but the boy later takes back his offer because other boys are saying mean sexual things to Jerri and she does nothing about it. So Tamela tells her she was a victim of sexual harassment and she needs to stick up for herself. Jerri later starts liking another guy, but is afraid it will end soon because of the other guys harassing her.
A new student comes to Flatpoint High, who turns out to be a bully who everyone is afraid of. When Jerri stops a fight with the bully and her friend Tammy, the bully schedules a fight for after school. Everyone keeps telling Jerri that she shouldn't fight and find peace, but Jerri feels she should live by the street code and fight. Geoffry gets a bully of his own when a homosexual hater substitute confronts him.
Winona Ryder stars as Fran, the coolest girl in school, who makes a bet that she can make Jerri so cool that even Brent Brooks (Paul Rudd) will ask her out.