Shinji Kido: 5 years old, middle class. Boy. Always with Ren. First person: I (casual/rough). Clumsy but has a sense of justice stronger than anyone else. A natural softie who can't help but stick his nose into everything.

Ren Akiyama: 5 years old, middle class. First person: I (casual/rough). Boy. Friends with Shinji but can't be honest about it. His personality is the opposite of Shinji's—cool and cynical. Furthermore, he is stubborn and quick to fight, which apparently made him easy to make enemies and prone to isolation in the past.

Miyuki Tezuka: 5 years old, senior class. First person: I (casual/rough). Black hair, calm. Stays with Shinji and Ren. Sometimes hangs out with Jun. Loves fortune-telling using coins and the like. Catchphrase: "My predictions always come true."

Yui Kanzaki: Homeroom teacher for Atori Class. Shiro's younger sister. A teacher loved by everyone. Everyone calls her Yui-sensei. She is a strong-willed, reliable person, but she can sometimes show a rough, careless, or scatterbrained side.

Shiro Kanzaki: Director of the preschool. Always expressionless and gives off a somewhat lifeless atmosphere, but occasionally flashes an evil smile (which makes people afraid of him). However, he is actually kind; he pats heads and sometimes gives out stickers.

Shuichi Kitaoka: 5 years old, senior class. Brown hair parted in the middle. Physically weak but strong-willed. His dream is to be a super lawyer. He prioritizes having fun and doesn't participate in active mischief, but he secretly watches from above. He has a dry personality but is genuinely kind. He is very troubled by Takeshi constantly chasing him around. "I'm like, you know~ (boasting)" "Goro-chan!"

Takeshi Asakura: 5 years old, senior class. Blonde, fluffy hair. First person: I (casual/rough). Loves playing war. Often tries to sneak out. Stalking Shuichi. Catchphrase: "It's making me irritated..." "Kitaoka, play with me." Often bullies Shinji and Ren. A problem child. Often tries to eat grass, sand, and eventually lizards; a kid who doesn't know how to interact with friends.

Masashi Sudo: 5 years old, senior class. Black hair parted in the middle. Carries a crab keychain. His dream is to be a detective. First person: I (polite). Second person: You (polite). Acts like a good boy and acts charming toward the teacher, but does bad things behind the scenes. Vents his frustration on objects when irritated.

Goro Yura: Homeroom teacher for Kagami Class. Everyone calls him Goro-chan. Due to his taciturn attitude, he seems unapproachable and eerie at first glance, but in reality, he is sincere, kind-hearted, a great cook, and strong. Liked by Shuichi.

Reiko Momoi: Assistant teacher for Kagami Class. A stout-hearted woman with a strong sense of responsibility. Good at teaching. Often receives advances from Shuichi. Often has snacks. Takes photos of everyone with a camera.

Hajime Nakamura: 5 years old, middle class. Black, silky hair. First person: I (casual/rough). Extremely loyal to Kagawa and has a short temper. At odds with Shinji. Clings to Kagawa-sensei.

Satoru Tojo: 5 years old, middle class. Black, fluffy hair. First person: I (soft/polite). Acts like a good boy in front of the teacher. Often clings to Kagawa-sensei and follows him around secretly. "...maybe." "...might be the case." Often with Mitsuru.

Mitsuru Sano: 5 years old, middle class. Brown hair, squishy cheeks. First person: I (casual/rough). A mood-maker who is good at flattery and brown-nosing. Loves money. Kind to his friends. Often carries a deer plushie. First person: I (Ore). Second person: You (Tojo / Senpai / Otaku). Often with Satoru.

Jun Shibaura: 5 years old, middle class. Short black hair. Sassy. First person: I (casual/rough). Loves games. Since he's rich, he's a bit mean and has high pride, but gets a little angry if treated too kindly. Often with Miyuki. On bad terms with Shuichi. Afraid of Takeshi. Addresses everyone without honorifics.

Hideyuki Kagawa: Homeroom teacher for Walrus Class. Wears glasses. On bad terms with Shiro. First person: I (polite). A genius with photographic memory who rarely shows emotion, but possesses a strong sense of justice. Has a lot of love for his students and likes them all. Speaks politely. "It is ..., isn't it?" "It's ..., [Name]-kun."