Bertrand Claverie, a young teacher much loved by his students, commits suicide by throwing his car off a cliff. Bertrand's class is in shock but one student, little Fabien Moreau, a strong-willed 10-year-old, seems to hold the secret of his teacher's death.

Eight-year-old Félix Reynal has just arrived at Louis-Lumière School. He only sees his father, Vlad Mankievic, in secret because he's a thug wanted for murder.

While picking up her daughter, Mylène Delorme knocks over 10-year-old Mehdi on his skateboard. Panicked, Mylène flees, leaving the young boy unconscious. While Mehdi, in a coma, struggles between life and death, the police actively search for the hit-and-run driver.

Eight-year-old mixed race Alison suffers from her parents' disagreements. Her Congolese father Virgil can no longer stand the racism he faces in companies while his French wife, Charlène, is succeeding in her career.

Nine-year-old Muriel Miller is a sickly child who regularly has fainting spells. Her overprotective mother bars her from participating in activities and outings. When Lisa Rivière discovers that Muriel was absent from her checkup, she decides to take a closer look at the child's family. What is this visibly disturbed and omnipresent mother hiding?

Annabelle Cartier, the school's youngest teacher, is an avid online dater. During a date, she rejects an unstable young man, who is now fixated on her. Frightened by his harassment, she calls the police, which doesn't discourage the lovesick man. On the last day of term, he manages to enter Annabelle's classroom and, armed with a revolver, takes the students and their teacher hostage.

As they leave school, African girl Mia and her mother are met by the police to be deported and sent back to their country, where their lives are in danger.

In a supermarket, ten-year-old Ismaël pulls a revolver on the sales manager, whom he seems to know well. Will he pull the trigger?

Against the advice of her colleagues, Lisa agrees to take young Enzo, a temperamental, quarrelsome, and self-destructive child who has been expelled from all the surrounding schools, into the Lumière School.

Nine-year-old Lucas's mother died on 9/11. One day, a young woman approaches the little boy and tells him that his mother is not dead.

In her father's eyes, ten-year-old Marilyn has a bright future ahead of her: singing, acting, dancing... Marilyn's whole life revolves around this crazy dream: to one day become a star.

Lou Riviére has gotten into the habit of chatting with her aunt Audrey online, secretly from her mother... until the day, a dangerous individual uses Audrey's identity to get closer to the little girl.

During a school trip, a Lumière class finds themselves embroiled in a gas station holdup. The cashier threatens the hooded man with a gun. A little girl named Margot intervenes to prevent the cashier from shooting the robber. Who is the little girl is trying to protect?

Abandoned by his father, Lorenzo has always lived with his mother and stepfather Marc, whom he adores. But when Lorenzo's mother separates from Marc, he no longer has any rights over the child. A new partner, Sébastien, moves in with them, and from now on, Lorenzo is no longer even allowed to meet Marc to play soccer. Lorenzo rebels at being tossed around at the whims of adults.

Twelve-year-old Noah has only reached the fifth grade after repeating a year and can barely read or write. The undisputed leader of the playground, Noah is hiding a big secret: at his age, Noah still wets the bed every night. In his evening remedial class, Audrey becomes attached to the boy and tries to pull him out of the abyss he's sinking deeper into every day.

Alice seems disturbed, and has even gone so far as to steal cakes from the local grocery. Her grandfather, who is raising her, remains unreachable and invisible.

Autistic Nino's arrival at Lumière doesn't go unnoticed. He's seen as weird by the children, except for one, Djibril, a clever little Arab boy who chooses to befriend him. Nino lives with his father but dreams of finding his mother, who abandoned him when he was little. Djibril decides to help his friend in this endeavor.

Violeta, a little Gypsy girl that Lucille manages to enroll at Lumière, is becoming increasingly integrated. A strong friendship has developed between Lucille and Violeta. However, during a police raid on the Gypsy camp, the little girl's uncle and mother are arrested for trafficking in false papers, a tragedy that has shattered the fragile balance Lucille had built.