One Berlin secondary gives the lie to claims that schools with many immigrant pupils cannot curb violence.
Just over a decade ago, the Werner-Stephan secondary school in Berlin's Tempelhof-Schoeneberg district was considered one of the worst in the city, with violence an everyday occurrence. But now the Hauptschule - a school for lowest-ability children - is one of the most sought-after in the capital for pupils who fail to make the grades for the more academic grammars.
Almost all its students, who come from 40 countries, leave with a high-school certificate.
Headteacher Ruth Jordan said a key factor in its success is involving students in setting the rules and running the school. "As a result, they are more prepared to accept regulations that have been brought in by teachers," she said.
Each year a group of student representatives meets with teachers to draw up a new list of "10 commandments" for all pupils to follow. Currently these include: "I will respect my fellow pupils regardless of what nationality they are" and "I will not bring any drugs or weapons or right-wing items to school".
The commandments forbid students from using violence as a means to solve problems. Mrs Jordan said: "We have very few problems with fights in the school yard, because the directives to avoid such confrontation come from the pupils themselves."
If a fight does break out, it is the 80 pupil "conflict mediators", not the teachers, who pull the aggressors apart.
Around 50 per cent of pupils are non-native Germans and ensuring ethnic integration is crucial, Mrs Jordan said. "We offer extra language classes for students of mixed ages who come to our school and cannot speak German.
Quite often it's frustration at not being able to understand that leads to aggression and violence."
Many of the language lessons are conducted at the same time as other lessons, such as art, so that the pupils are learning vocabulary in context.