Chicco, Massimo, and Bruno Sacchi are on vacation in Tropea with Sharon Zampetti. Due to an agency error, the Zampetti family and the Sacchi family (Bruno's), find themselves renting the same house. Unable to change, they mutually decide to vacation together. Bruno also invites his other friends. Over the course of the summer, the kids become rivals to a young nobleman, Prince Leopoldo, with whom Sharon has fallen madly in love. But eventually, the kids discover that the Prince is penniless and only wanted to marry Sharon for money.

During their vacation, the "3rd C" kids are hired as new faces by a ramshackle film crew filming a ridiculous remake of "Indiana Jones" in Tropea. For our eight inexperienced extras, the glories of the movie world will be a huge disappointment.

Chicco, Massimo, Daniele, and Bruno are planning a major heist at Leopardi High School. They must be very careful not to be discovered because their prank, even if it's for a good cause, is punishable by law. Their goal is to falsify the final exam transcripts and promote poor Tisini, who has unfairly failed her class. The students find a valuable collaborator in Mauro, who helps them falsify the report cards.

Mauro has found a job as artistic director at a private TV station of dubious standing. He tries to involve his friends at 3C in his new and exciting venture, entrusting them with the task of managing the schedule (the day's programs) and promoting the most interesting television programs with the aim of increasing their audience.

The boys of Class 3C buy a luxurious and enormous apartment for a paltry sum. Naturally, none of them questions why such a large house costs so little. Soon, the boys discover the reason: the house, which once belonged to a magician, is haunted. The boys, in turn, are mysteriously kidnapped by Igor, the deceased magician's assistant, who aims to own the apartment. Unmasked, however, Igor ends up working as a butler.

Sharon dreams of becoming a great fashion designer, internationally renowned. To showcase her talents, the young woman organizes, with the limited resources she has, a fashion show showcasing her own designs. But at the last minute, she's short of two models. How can she fix this? Massimo and Chicco, out of love for Sharon, agree to play supermodel and, dressed as women, make quite an impression. The Italian teacher, in fact, is fascinated by "Massima."

The kids in Class 3C become babysitters and take care of a terrible eight-year-old for a whole week. It will be the longest and most tiring week of their lives. They realize how difficult and complicated "being a parent" is, especially when dealing with "today's kids," who are far too smart and mischievous. Of course, generations change, and nothing of the innocence of the children of old remains.

It all happens to Bruno! This time, the boy discovers he has a double, but a very dangerous one: a criminal wanted by the police. The shy and clumsy Bruno is continually mistaken for the real "bandit," who, in turn, to escape the police, tries to impersonate the boy from 3C.

The couple's crisis spares no one, not even two legendary, inseparable, eternal lovers like Daniele and Rossella. The two sweethearts suddenly realize that monotony is destroying their relationship, with no more emotions, nothing left to say. The only solution is separation. The couple tries to comfort Daniele and Rossella by suggesting other potential partners. However, every effort seems futile, and the couple begins to wonder if Daniele and Rossella will ever be able to become truly single and live apart.

The charming Bruno discovers the joys and sorrows of love; for the first time in his life, he feels truly happy because he's fallen in love. But after Bruno develops a terrible crush on a girl, he's never been the same, and everyone, parents and classmates, are stunned by his "strange" behavior. Unfortunately, on the day of the official engagement, a terrible thing happens: Bruno discovers that his sweetheart is already engaged. Poor Bruno, seduced and abandoned, must try to cope with this terrible blow.

The students of Class 3C have spent unforgettable years together. Even after school, they promise each other they will never change and will always be friends. But let's try to imagine them in ten years. Time changes things and people; will the students of Class 3C, as adults, be able to remain the same carefree selves they once were? Years have passed and the former students of Class 3C meet again... but perhaps it's just a dream.