• Teacher Helena Fernandes (
Rosanne Mulholland): The protagonist of the
telenovela. She is a 30-year-old teacher who teaches the third grade at the Escola Mundial. Beloved by all her students, Helena is kind and protective. • Cirilo Rivera (
Jean Paulo Campos): Is a poor black boy. He is better known by the students for being gullible and is often fooled by Paulo, Mário, or Kokimoto. He has a crush on Maria Joaquina. • Maria Joaquina Medsen (
Larissa Manoela): She is a rich, racist, and somewhat arrogant girl. Maria constantly brags about her father, a prominent yet humble doctor, and looks down on everyone of a lower social class, especially Cirilo, for being black. However, she helps her classmates sometimes and ends up becoming Cirilo's friend. • Valéria Ferreira (
Maisa Silva): A smart, rowdy, and sometimes mistrustful girl and Davi's girlfriend. She is always making jokes about other students during class, causing everyone to laugh. • Jaime Palillo (Nicholas Torres): Jaime is a chubby boy who doesn't understand the lessons at school. Despite being a little slow in his studies, Jaime is very gentle and always ready to help others. • Carmen Carrilho (Stefany Vaz): She is the poorest student in Helena's class and suffers from her parents' divorce. When Carmen has appendicitis and is operated on by Maria Joaquina's father, her operation brings her parents together again. • Davi Rabinovich (
Guilherme Seta): Valéria's Jewish boyfriend. He is called a coward by his classmates. Davi has a pet turtle named Relâmpago () and once wished to make him into soup to cure Firmino, who was sick. • Laura Gianolli (Aysha Benelli): This chubby and gluttonous girl dotes on things being "romantic". Some students make fun of her weight. • Daniel Zapata (
Thomaz Costa): The most intelligent and correct student in the class. He is good friends with Maria Joaquina and Margarida Garcia, and he is the president of the boys' club. • Paulo Guerra (Lucas Santos): Paulo is the most troublesome in the class, a bully who makes jokes about Cirilo and Laura and mistreats his little sister Marcelina. • Mário Ayala (Gustavo Daneluz): Mario lives with his father Germano Ayala, his stepsister, and his mean stepmother Natália Ayala. He studies at the Escola Mundial after being sent out of another school for misbehaving. On his first school day, Mario behaves so badly that Helena cries. In the course of time, his demeanor gets better and he becomes friends with everyone. He loves animals and once adopted a street dog and named it Rabito. • Marcelina Guerra (Ana Zimerman): The sister of Paulo Guerra. Her brother hates her, but she still loves him and says the bad things he does are not his fault. She is usually made fun of because she is the smallest in her class. • Adriano Ramos (
Konstantino Atan): He has crazy dreams, which make him sleep during class time. In his room, he likes to talk to an old sock, named Chulé (), and a chair named Senhor Cadeirudo. • Alícia Gusman (Fernanda Concon): The tomboy of the class, she wears mismatching clothes, enjoys radical sports and rides her skateboard to school. • Bibi Smith (Victória Diniz): She has an American accent because she lived in the US and mixes English words in with her Portuguese. She is the best friend of Maria Joaquina. • Jorge Cavalieri (Léo Belmonte): The richest boy in the class and Maria Joaquina's neighbour. Jorge is very proud and acts superior to his classmates, who don't like him but they still hang out with him. • Margarida Garcia (Esther Marcos): She is a girl from the interior who comes to live in São Paulo in the company of her mother. As a characteristic, she wore a cowboy jacket and boots. She also had a conflict with Valéria, making her jealous of her friendship with Davi, but as she time becomes friends. • Kokimoto Mishima (Matheus Ueta): He is very small but smart. He wears a Japanese band on his head (a
hachimaki) to say that he is Japanese. He is friends with Paulo Guerra and helps him with almost all his plans, but he never gets in trouble for doing them. • Tom (João Lucas Takaki): He is in a wheelchair from a car crash which killed his father. He lives with Ms. Glória, his mother. Tom was scared to go to school because he thought the students would make fun of him, but the students of the third grade showed this wasn't the case. • Teacher Suzana Bustamante (
Lívia Andrade): A fourth-grade teacher who substitutes for the class when Helena has a car accident. She is in love with Renê, the music teacher, and tries to sabotage his relationship with Helena. She is also friends with Principal Olivia and gossips about Helena. • Teacher Renê Magalhães (Gustavo Wabner): The Escola Mundial music teacher. He has been friends with Suzana since college and has a crush on Helena. The students of the third grade love him, so they always behave during his class. • Firmino Gonçalves (Fernando Benini): He was born in Portugal and came to Brazil when he was older. He is a widower and the Escola Mundial groundskeeper, where the students are like the children he never had. • Graça (Márcia de Oliveira): The maid at Escola Mundial. She loves to hear everything everyone says and voluntarily passes on information to Helena. She complains her job is not good. She hates Suzana and says she is a snake. She is a great friend of Firmino. • Principal Olívia Veider (Noemi Gerbelli): She thinks everything can be solved with discipline. She hates Helena and believes Suzana's gossip about her. ==Cast==