She is fundamentally meddlesome to a fault, and in the early stages, her desire to stand out above everyone else is clearly displayed. Because of this, she is the top troublemaker, causing even more nuisance than Mujin.

He is tall for his age and always has a bright smile on his face. However, due to his quiet and timid personality, along with his perpetually sleepy-looking eyes, he is quite introverted. His voice isn't very loud, and he tends to watch from behind rather than stepping forward among his friends. He has a kind and soft heart, so if someone scolds him, he becomes disheartened and quietly goes back to his seat. Male

Female Kind-hearted. She was chubby when she was younger.

Male A prankster. Loves running around and playing. He only tends to listen when the teacher gets angry. He enjoys teasing others.

He is popular among his peers because he has many strengths, leading to many episodes where the girls insist on being paired with Pureum whenever they have to pick partners. He is the only 'normal' person in the work who doesn't cause trouble or have character flaws. While others show immaturity—such as being overly meddlesome, poking their noses into everything, or picking fights based on a child's typical selfish behavior—Pureum has never done anything selfish and only performs sensible, good deeds. Thanks to Pureum's mediation and kindness, viewers can find peace of mind even when other characters are frustrating. He is highly praised by the audience. He is fundamentally kind and the most mature. The Purple Class teacher has praised Pureum's personality several times, and he always takes charge of mediating when the children fight. Even Lee Mujin, who is famous for being stubborn, listens to and accepts what Pureum says, showing his strong leadership. He is a child who grew up quickly because he doesn't have a mother; his episodes often focus on him being so mature for his age that he holds back tears even when he wants to cry. While other characters represent the raw, selfish side of children who are not yet fully socialized, he is exceptionally precocious. Male

She is a child from a multicultural family, born to a Korean father and an Italian mother. She is the most athletic among the girls and has a strong sense of duty to protect the girls from the boys. Female

He is a child from a multicultural family, born to a Korean father and a Vietnamese mother. Male He likes Chaerin.