Geraldine Antonia "Jerri" Blank (Amy Sedaris) was born in 1953 to a drunken Aramapu woman, who traded her for a pitcher of beer.
Jerri's bigotry is always presented as an example of her stupidity and ignorance, and she has never been violent towards any of the minority groups she insults; however, in the twisted, valueless world of the show, her views are never really contradicted or punished, and she is inevitably allowed to carry on with her behavior.
At the end of "Yes, You Can't", she is seen playing the drums for "Carry On Wayward Son", perhaps leading the viewer to believe that she is a talented drummer as well.
She also does not seem to be above any form of inappropriate intercourse, once saying that she and a boy she had just discovered was her son could still make out, or continuing to have sex after being diagnosed with syphilis, gonorrhea, and crabs.
Jerri seems to have quite a collection of wigs (her hairstyle changes constantly, growing longer or shorter within a single episode) and wears an inordinate amount of makeup.
Despite all the effort she puts into her appearance and her own belief that she is quite sexy, over the course of the series she is frequently mistaken for an old man.
In the series finale, "The Last Temptation of Blank", Jerri's big heart caused the most popular girl (Winona Ryder) in school to run off to become a junkie whore like her, and later she, Principal Blackman, Mr. Jellineck, and Mr. Noblet decide to become whores after they burn down the school, as they feel this life direction "beats teaching".
Guy Blank (Roberto Gari, Dan Hedaya in the film) is Jerri’s adoptive father, shown only in a voiceless, frozen state during mid-action (for example, carving a turkey, driving a car, or participating in a father–daughter sack race practice).
In this episode, he is mauled to death by dogs, traumatizing Jerri but allowing her to learn the lesson that "you can never really lose your parents, unless of course they die, and then they're gone forever."
Evidence points to Guy Blank as being a racist; he evidently calls Principal Blackman by “an ugly word,” requested that “no darkies” attend his funeral, and owned some Klan robes (Jerri discovered them in his closet after his death, although she was distracted and didn’t seem to notice them, or else didn't care) - this may also have contributed to Jerri's racism.
Sara Blank (Deborah Rush) is Jerri’s alcoholic stepmother who favors her son over her stepdaughter and has an ongoing affair with Stew, the meat man.
She is quite disdainful of Jerri (in the Strangers film, she told Stew, “I wouldn’t want you to think that that slithered out of my womb.”), but she delivers most of her lines with a sugary sweetness that hides much of her true venom.
Derrick Blank (Larc Spies, Joseph Cross in the film) is Jerri’s junior varsity jock half-brother who is suspected of being a closeted homosexual.
In “Is My Daddy Crazy?”, when Jerri was hosting a sleepover, his mother urged him to hide in the closet and masturbate to the scene of high-school girls having a pillow fight, but he declined in favor of reading his “gladiator magazines.” He was, however, entranced by guest-star Winona Ryder in the series finale “The Last Temptation of Blank”.
On one occasion, after one of their targets verbally shot them down, Derrick suggested to his friends that they “go watch some gay porn and get our hate back!” He was in every episode except “Yes, You Can't”, “The Blank Page”, “To Love, Honor, and Pretend”, and “Bully”.
In “Is My Daddy Crazy?”, he went temporarily insane and coated the house with cheese before his reflection fired him, and he was cured by Jerri drilling a hole through his skull.
Even before Guy's death, he filled the role of father to Jerri, first by being unthoughtful and emotionally abusive like Sara, and then by being loving and attentive when he became completely insane.
Stew’s name is intentionally spelled like the food, as is confirmed by his work shirt which has S-T-E-W on the name tag (seen in the film and in episodes such as “Feather in the Storm”).
Charles "Chuck" Noblet (Stephen Colbert) is a bitter history (usually) teacher at Flatpoint High School.
He seems to make up almost everything he teaches, stating that in light of the Japanese American internment, "it's important that we never forget the atrocities that the Japanese committed against our boys",[1] that "following his violent revolution, Gandhi was devoured by his followers",[2] that "the tragedy" of Martin Luther King Jr.'s life "is that all this footage is in black and white; imagine how powerful it would have been in color" (and adding that he is "not sure" what happened to King),[3] that "the tragic irony of the Trojan War" is that "though it was fought over Helen, who was young and beautiful, by the time they rescued her ten years later, she was old and ugly" (moral: "an ugly woman is never a reward"),[4] and that "the Opium War was fought in 1840 to 1842 between the Chinese and the Mexicans".
The two sometimes consummate their affair through roleplaying: pretending to "bump into each other" for the first time, introducing themselves (with much discussion of their wives and children), and ultimately sneaking off somewhere to have sex.
Geoffrey Jellineck (Paul Dinello) (pronounced JOFF-ree, as opposed to the more common JEFF-ree) is Jerri’s flamboyant, insecure, narcissistic art teacher.
Jellineck is superficially a very kind and sunny person (in the film he tells Jerri, “You can talk to me: I’m an authority figure, but I have the mind of a child.
Paul Dinello has said that this aspect of the character was based on the personalities of teachers and professors who try to be "one of the kids" and think they're succeeding, but in reality are regarded as slightly creepy.
Duffy also pops up in other places throughout the show, such as a secretary in the doctor's office in "Jerri’s Burning Issue” and a nurse in “Hit and Run”.
In the first season especially, he had a huge crush on Jerri and was not above spreading rumors about her love interests to stop her from seeing them (as in “Bogie Nights” and “Let Freedom Ring”).
In most cases, she is grounded and sane, providing a voice of reason and normalcy in the odd social structure of Flatpoint High and tries to give Jerri good advice, though she never takes it.
Often he is spontaneously beaten up by jocks for no definite reason, though his beatings often follow particularly flamboyant dialog or actions of Jimmy’s (his repeated phrase I'm so jazzed!