The last three weeks of school life have begun: After the Abitur, Germany's leaving certificate, the friends and schoolmates of Gymnasium Kerkheim (Kerkheim High) will not see each other again so soon. It is a hard time for Markus and his girl Sandra from a lower grade, as he wants to hang out with his old friends, whereas she wants him to be there for her. It's an even harder time for Dirk, who is to be expelled from school if he fails the math exam that is coming up around midday, and it is the hardest time for Michael, who is a perfect pupil, but has no fun in life at all - and doesn't even know it yet. When Steven calls out a party to celebrate his letter of exemption from the army, they all get together for one of the last real cool events ever.
Poor Bibi - due to her bad marks in maths she has to spend the whole summer in the boarding school of Altenberg to scrape through a series of exams - otherwise she'd stay down in school, being forced to repeat the year. No camping, no white-water rafting, no vacation at all. So it doesn't surprise anyone that the young witch is quite disgruntled when arriving at Altenberg Castle. Her roommate is a touchy unpleassant fashion victim and headmaster Quirin Bartels is so muddle-headed that he can't even remember the names of his students properly. But then Bibi makes friends with Elea, a girl wheelchair-bound since a terrible accident where she also lost her beloved parents. Now Bibi is determined to help the sensitive Elea, searching a way to heal her from her palsy legs.
A boy who was once a perpetual outcast finds friends in a new boarding school, united with his new peers gets involved in a heated rivalry with a group of students from a neighboring school.