Characters

Chiyo Mihama (Chiyo-chan)
Chiyo is considered a child prodigy. She skipped grades 5th-8th because of her intelligence, and is now a high schooler. She's overly adorable and seems to have no weak points. Her family is incredibly rich, so every summer the gang go to her summer home. Chiyo-chan seems out-of-place in high school, and is seen as the class mascot. For some reason, she and Osaka get along well (talk about polar opposites!).

Tomo Takino
Tomo is hyper and on the brink of going insane. Her energy seems to know no end. She likes to challenge people, which range from running to cuteness to...just plain weird. Her grades are below normal, but passes thanks to her copying methods. Tomo has been friends with Yomi since kingergarten, so she knows more about her than the others do...and some stuff Yomi dreads Tomo sharing. She seems to be a younger version of Yukari.
Ayumu "Osaka" Kasuga
Ayumu, who now holds the infamous nickname of Osaka, transferred to the class shortly after Chiyo-chan. She, obviously, comes from Osaka, which is how she got the name (from Tomo). She is spacey, and comes up with very odd comments about very odd things. Despite this, Osaka is a sweet, kind girl and gets the best grades of all the Numbnuts. Her surprising talent, though, is that she holds an inner genius when it comes to solving logic riddles.
Koyomi "Yomi" Mizuhara
Yomi is considered to be the most "normal" of the Azu group. She has a level head and is fairly mature. Most of her speech consists of critizing Tomo for being an idiot. Yomi is fairly atheltic, and has excellent flexibility. She's always going on odd diets, though, which is how Tomo critizies her. Yomi seems to be a younger version of Kurosawa.
Sakaki
Sakaki is tall, quiet, and athletic. Most people think she's cold and scary, yet she has an obsession with animals. Unfortunately, none of the animals like her, and they either bite her hand or run off. Sakaki really likes Chiyo-chan, mainly because of her cuteness. She wishes she could be cute like Chiyo instead of tall (and pretty!). The only animals that don't bite her are Mr. Tadakachi and Maya.
Kagura
Kagura is like an atheltic version of Tomo. She's not that great at schoolwork, and is only good at P.E. and Health. Tomo and Kagura make a deadly pair, since they have huge battles in the beginning...together, they're just loud and obnoxious. Kagura considers Sakaki her rival, but the two never rarely do anything competetive (except for an eating competition). She joins Yukari's class in the second year. Popular belief says Yukari really wants to win the Sports Festival.
Yukari Tanizaki
Yukari is an English teacher, "so she'll marry and get richer". Nah, that's her own diluted fantasy. She's the girls' teacher for their three years of school. She and Kurosawa have been friends since high school, and she seems to have something on her. Yukari isn't exactly teacher material, and acts more like a student than an adult. Well, she can speak English, so maybe she has a few strong points after all...
Minamo "Nyamo" Kurosawa
Nyamo is the school's gym teacher, and is always the object of Yukari's rivalries. The two have been friends since high school, but you could only guess it by the way they always hang out with each other. She is a level-headed, keep-it-cool teacher whom many of the students look up to as a role model. Nyamo has some sort of secret dealing with a love letter, which is why she can never tell the students what Yukari was like back in high school...