Having visited Dachau, I can attest to the power of such visits:

It was not the execution wall or the electric fence or even the description of the smell of human flesh burning day and night that made the teenagers stop cold.

It was the bunk beds.

In their wooden ordinariness, they spoke to the 10th graders visiting the former Nazi concentration camp of Sachsenhausen as no history book had. “This is how they lived,” whispered Damian, 15, his eyes taking in the tightly packed rows of ladderless three-level bunks.

When Jakob Hetzelein, a history teacher in a working-class district of northeastern Berlin, decided to take his students to Sachsenhausen, a short suburban train ride from the German capital, he was not sure how it would go down.

His lessons on Nazi Germany had met muted enthusiasm. In a mock election in class, several students had supported the nativist Alternative for Germany party. One boy was recently caught scribbling a swastika on a friend’s jacket. Another does Hitler impressions when he thinks Mr. Hetzelein is not looking. Left index finger under his nose, right arm extended.

And then there are Mahmoud and Ferdous, recent refugees from Egypt and Afghanistan, where anti-Israel sentiment routinely blends into anti-Semitism and sometimes Holocaust denial.

Mr. Hetzelein, 31, who used to teach in a vocational school where nine in 10 students had Turkish or Arabic backgrounds, knows about casual anti-Semitism. “Jew” is a popular insult on some soccer fields in Berlin.

“It has become harder to teach history,” he said.

Teaching history is a pillar of national identity in postwar Germany. That is why Sawsan Chebli, a Berlin state legislator with Palestinian heritage, recently came up with an idea that is radical even by the standards of a country that has dissected the horrors of its past like no other: make visits to Nazi concentration camps mandatory — for everyone.

“This is about who we are as a country,” she said in a recent conversation in Berlin. “We need to make our history relevant for everyone: Germans who no longer feel a connection to the past and immigrants who feel excluded from the present.”

Ms. Chebli’s proposal comes at a time when Germany is grappling with the creeping rise of two kinds of anti-Semitism and as the Jewish community, now numbering about 200,000, is once again nervous.

Neo-Nazis have been emboldened by the arrival of Alternative for Germany, the first far-right party to break into Parliament since World War II. And there are concerns that the recent absorption of more than a million immigrants, many from the Middle East and many Muslim, has inadvertently created incubators of a different kind of anti-Semitism — one hiding behind the injustices of the Israeli-Palestinian conflict but often reverting to hateful old stereotypes, too.

It was the sight of Arab immigrants, including Palestinian-Germans like herself, burning an Israeli flag underneath the Brandenburg Gate in December while chanting “Death to Israel” that moved Ms. Chebli to speak up.

Since then, other disturbing stories have emerged in the German news media: an Afghan boy greeting his teacher with “Heil Hitler” and proclaiming that he, too, was Aryan. A group of Syrian refugees calling the Holocaust “a Jewish conspiracy,” explaining that they had learned that in school back home.

The reaction in Berlin, where there are strict legal prohibitions of Holocaust denial and Nazi propaganda, has been swift. The government announced that it was appointing its first-ever anti-Semitism coordinator. Some in Chancellor Angela Merkel’s conservative party have urged the immediate deportation of anti-Semitic Muslims.

Günter Morsch, the director of the Sachsenhausen memorial, says he does not think that is helpful. “We cannot allow this debate to create another form of racism,” he said. “What about the Germans who are anti-Semitic?”

Nine in 10 anti-Semitic hate crimes reported in Berlin are committed by German citizens. And for all the seeming contradictions, there is a common denominator between Muslims who espouse anti-Semitic views and those on the far-right (who also hate Muslims), Mr. Morsch said.

“Anti-Semitism correlates more closely with educational background than with ethnic background,” he said, citing empirical studies.

Ms. Chebli says that visiting a concentration camp is no panacea, but that it can help. She visited one as a young woman. The experience changed her, she said.

“It is a powerful way of keeping memory alive and giving meaning to our mantra of ‘never again,’ ” Ms. Chebli said. “But we need to get back to the essence of what this is about: It’s about standing up for human rights and the rights of minorities — all minorities.”

Muslims, too

During their visit to Sachsenhausen, the teenagers huddled around their guide in the vast triangular courtyard of the camp, its perimeter still dotted with watchtowers.

Sachsenhausen was no death camp, although tens of thousands of inmates are believed to have died here; those were built by the Nazis outside Germany. But it was the nerve center of two dozen major concentration camps run by the Nazis.

From an inconspicuous office building in one corner of the camp, civil servants decided what kind of medical experiments would be conducted, how many executions would take place and how much cyclone B gas would be delivered to the gas chambers in Auschwitz. “Desk perpetrators,” the guide, Mariana Aegerter, calls them.

“Does anyone here know who was imprisoned here?” she asked the class.

Nelson, a boy with shoulder-length hair, tentatively raised his hand. “Jews?”

There were Jewish prisoners in Sachsenhausen. But unlike in the death camps, they were a minority. Of more than 200,000 inmates over the years, some 40,000 were Jewish. Many died here.

The Nazi regime targeted many, Ms. Aegerter explained, like communists, clerics, homosexuals, Roma and the disabled. But also those considered “antisocial”: The homeless, the jobless, those on social welfare, and boys with long hair — Ms. Aegerter’s eyes lingered on Nelson — or with too many girlfriends, or with a weakness for American music, like Jazz or swing.

By the time Sachsenhausen was liberated, she said, nine in 10 prisoners were foreigners, coming from 45 countries. There were Muslims, too.

“Muslims, too?” Ferdous said later. “I did not know that.”

Building bridges

Ms. Aegerter, a young historian, says her central aim during tours of the camp is to bring to life what is an empty space, to make students visualize life there, and ultimately to create a bridge between the visitor and the prisoner, between the present and the past.

“Our most powerful tool,” she said, “is identification.”

Recently, a young Syrian had asked a fellow guide, “Why do you turn your torture chambers into a museum?”

To make sure we will never have torture chambers again, he had replied.

The boy had thought this over for a while. “We have torture chambers in Syria,” he eventually said. “Maybe, when the war is over, we should turn them into a museum, too.”

It is not always easy. Once, a Palestinian schoolgirl asked Ms. Aegerter, “Don’t you think that what the Jews are doing with the Palestinians today is the same as what the Nazis did with the Jews?”

No, she had explained, but that did not mean one had to approve of everything the state of Israel was doing. The girl seemed unconvinced.

Ms. Chebli comes across this all the time, she said. “I have Palestinians tell me: I had to leave my country because of the Holocaust and you want me to worry about anti-Semitism?”

She recounted the lukewarm reaction of one young man to her concerns about growing anti-Semitism. Born and raised in Germany, he does not see himself as German because, he says, Germans do not see him as German.

“Of course, anti-Semitism is important,” he had told her, “but what about the racism I experience every day?”

To win over young Muslims for the fight against anti-Semitism, Ms. Chebli said, Germany has to fight Islamophobia, too.

“It’s much easier for me to persuade a young Muslim of the relevance of the Holocaust if I acknowledge their own experience of discrimination and create that link,” Ms. Chebli said.

Sometimes, creating a link with young Germans is just as tricky, Ms. Aegerter points out.

Now 34, she grew up in the eastern state of Brandenburg in the 1990s. Swastikas were a common sight in her town: Scrawled on the inside of toilet cubicles. Graffitied onto walls. A boy in her class had tattooed one on his shin. It was only after she and some friends had complained that the boy had been asked to wear long trousers during sports lessons.

These days, Ms. Aegerter has teachers on the phone who share their concerns about far-right tendencies among their students.

One teacher told her before a class visit that he had planned the trip specifically because he worried about three boys drifting into neo-Nazi territory. But on the day, all three called in sick.

“Sadly, that is no exception,” Ms. Aegerter said.

In some cases, she said, it is the parents telling teachers they do not want their children to visit a concentration camp.

When students do come, it can be transformative, said Mr. Morsch, who has been director of the memorial for 25 years.

“It would be naïve to expect a two-hour tour to turn neo-Nazis into anti-fascists,” Mr. Morsch said. “But give us a little time, and we can achieve a lot.”

He recalled a recent group of students from a vocational school that had a persistent problem with neo-Nazi graffiti. They spent several weeks in Sachsenhausen renovating one part of the memorial — but also working in small groups, dissecting drawings and letters of prisoners and creating their own exhibition.

“After they spend some time with us, the problem went away,” Mr. Morsch said.

Mr. Morsch still believes that camp visits should remain voluntary. He fears an obligation to come would take away from the learning experience.

Mr. Hetzelein disagrees. Whether schools or the law make the call, students rarely get a say. He grew up in Bavaria, the only German state where visiting a Nazi memorial is already required.

As a high school student, he went to Dachau, near Munich. Years later, he saw Auschwitz, the Nazi death camp in what is Poland today.

The cast-iron gates, the barbed wire and the sheer scale of it still haunt him. “It’s not enough to read books about it,” he said, “you need to feel it.”

A week after visiting Sachsenhausen, Mr. Hetzelein asked his students whether they thought their children should one day be made to visit a camp.

Of 22 students, 21 agreed. Among them: Ferdous, Damian and Nelson.