It was at the end of a German lesson and Günther Ferber's* day of teaching was almost over when an argument between two of his students escalated. One of them grabbed a knife that had been used in arts class earlier that day. 

"He rushed at the other student with the knife and shouted that he would kill him," Ferber told DW. The teacher instinctively placed himself between the two students. 

"He then attacked me with the knife. He was so angry that he just wanted to stab somebody."

Ferber, who is in his mid-thirties, got away with a minor injury. After a few minutes, he was able to calm down the attacker. "The whole situation was really shocking," Ferber says. The attacker was a teenager, not a very young student, so it would have not been easy to wrestle him down, he explains.

Violence at one in three schools

An isolated incident? No, says Udo Beckmann, Chairman of the Federation for Education and Training, Germany's second-largest teachers' union. He commissioned a survey of attacks on teachers at more than 1,300 schools. "The picture is very clear," Beckmann told DW. "The number of schools saying that teachers have been abused, threatened, insulted, bullied, or harassed has risen significantly over the past five years."

At every third school, he says, teachers have even been physically attacked.

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"This phenomenon of violence against teachers must be taken seriously," Beckmann demanded. He urged politicians to take action: "The education ministries should have to collect data and publish statistics on violent incidents. And above all, we expect the employers to stand behind the teachers, to support them both psychologically and legally in such cases and not treat this like it's just an individual's personal problem." 

Beckmann sees a need for more training to help teachers deal with bullying and violence, and for more support from other professions such as psychologists and social workers in schools. 

Paris attack fuels a debate

The issue of violence against teachers has not been high on the agenda here in Germany. But the attack on Parisian teacher Samuel Paty has put the spotlight on the danger teachers can face.

The French history teacher was decapitated by an alleged Islamist in broad daylight in a Paris suburb. Paty had shown controversial cartoons of the Prophet Muhammad to his pupils in the class to start a discussion on freedom of opinion.

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"This was an unbelievable act of violence," Lale Akgün told DW after the attack. Akgün, a trained psychologist and former Social Democrat member of parliament, warned it could not be ruled out that something similar could happen in Germany too.

She called for a public debate involving politicians, teachers and parents about what it is that schools should prioritize. "In my opinion, it is above all the teaching of values and the education of responsible citizens," Akgün said. She warned not to allow people with a patriarchal, often religious world view to suppress diversity of opinion in the classroom.

"The fact is that teachers sometimes experience outrageous things, experience bullying, experience threats. That is why a climate of fear develops," she explained. "This leads some teachers to self-censor and say: there are certain topics I do not treat at all. Why would I put myself in danger?"

Secondary school teacher Günther Ferber rejects the idea of self-censorship. "Teachers deliberately not dealing with such content because they feel threatened by some force or other? That does not reflect everyday life at the schools," he said.

"I am also a philosophy teacher and it is part of my daily work to let world views collide so that we can exchange ideas," he said. For him, it is important that teachers stand up for freedom of opinion and religion. "That is the basis of our constitution and talking about it is part of the curriculum." 

But Ferber does see a shift towards more violence in German schools too, and he admits that an attack like the one in Paris can not be ruled out. "We have also had school shootings in Germany. And I think there is a certain trend towards more open aggression," he said. Ferber feels it is important that schools do not allow hatred and violence to flourish.

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"There's generally a lot of pressure when you're in a room with 30 students on a hot summer day, for example, so you can't be surprised if one of them goes nuts at some point," Ferber explained. That's why he and his colleagues demand smaller classes, more teachers, especially more special needs teachers, who look after students with problems. "That way you can take the pressure off and prevent violence."

The student who attacked Ferber with the knife was temporarily expelled from school and had to do anti-violence training. But Ferber did not press charges against him.

"We teachers have been with the students for years. We don't want to harm them, we want to help them achieve something in life," Ferber said. This was, after all, why he decided to become a teacher in the first place, he added.

*Name has been changed for safety reasons at the interviewee’s request.