Frank Stimpel has to prove himself at his new school. He loses the respect of the class in the very first week and the police turn up - boss Aminata would love to throw him out again, but she needs the Alman teacher.
STIMPEL wants to curb the aggression among the pupils. He makes various attempts until it becomes clear who the real problem is: the passive-aggressive Alman teacher himself.
To increase his chances of becoming a civil servant, Stimpel founds a working group. But instead of action, the alman prefers to focus on theory. His colleague Yunus opposes this and founds a combat robot group that challenges Stimpel.
Stimpel becomes a tutor and wants to prove himself in the new role to his boss Aminata. Just when his student Leyla is in an emergency situation, the task becomes too much for him.
Stimpel finds out about an online ranking that rates the school's teachers according to their coolness. In order to gain the respect of the class, he tries desperately to loosen up.
To raise money for the school trip, Stimpel organises a school flea market. The ruthless competition between Sahra and him and the battle for supply and demand leads to a nasty situation.
Stimpel's attempts to improve safety at school fail due to resistance from the class. Stimpel Security, or StiSi for short, which he founded, aims to change this by any means necessary.
Stimpel, Sahra and the whole class go on a school trip to the forest - except for Stimpel, everyone finds it completely boring. The Alman wants to change that and provides a little thrill. But the forest has its own laws.
Stimpel's big day is coming up: The teacher's exam. His class's drug problem comes at a very unfavourable time. To show the youngsters the possible consequences, he carries out a self-test with fatal consequences.
