Nina Mayer was nearing her 25th birthday on March 11, 2009. She was a teacher at the Albertville school in Winnenden, a town near Stuttgart. In her free time, Mayer played the piano and helped disabled children.

"She had an unshakable belief in the goodness in this world, which would eventually make everything right," said her mother, Gisela.

That day in 2009 would be her last. A 17-year-old former student entered the school that morning with a Beretta pistol in his hand. It was his father's gun, but rather than properly securing it at home, he had covered it with a sweatshirt in the bedroom closet. His son, Tim K., would go on to shoot students, teachers and passers-by at the school and in town, killing 15 people and wounding 13 more, before turning the gun on himself. Nina Mayer was one of the victims.

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Confronting hate

Nina's mother initially felt "bottomless rage and hate" toward her daughter's killer. But she's changed over the years. "Today I see a poor young man eaten away by hate," she said. "Someone who had no joy in his life and therefore hated those who did. Now I view him with pity."

A few weeks after the shooting, she and others close to the victims founded a group that became the Foundation Against School Violence. Their goal is to prevent more tragedies like the one in Winnenden. The group works on prevention methods and counsels parents concerned about their children.

"It was an act by a single person and blame rests with him," Gisela said. "But those who weren't paying attention share some of the responsibility."

Locks and counselors

Gisela and her supporters have also been lobbying for stricter gun control in Germany. They have not been able to change legislation that allows hobby gun owners to keep their weapons at home and also possess large-caliber weapons. However, Mayer notes some progress, including unannounced inspections to ensure gun owners are properly storing their weapons. There is also more focus on prevention at schools, she said, with additional counselors on hand: "It's never enough, but at least it's something good."

Much has changed at the Albertville school itself. It has been remodeled and enlarged. A classroom now serves as a memorial for the victims. Doors also lock automatically during class time in an effort to stop attackers like Tim K.

'We can learn from what happened'

"Of course it can happen again," Sven Kubick, who has served as Albertville's principal since 2010, told DW. "We can only make security measures strong enough to be able to say that our students are as safe as possible."

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The memory of the shooting remains, Kubick said, despite the fact that an entirely new generation of students is now attending the school. Students there take part in a number of projects against violence and on social well-being.

"We can learn from what happened. We can try to work with students so that they get along with one another. That's what's possible here," Kubick said.

A lasting image

Prayer, candles, flowers and discussion characterize the 10th anniversary of the shooting, as they do every year, to remember the victims from that day. For victims' families like Nina's mother, Gisela, the pain is just part of life.

"It's always with me," she said, though she is comforted by the image she has of her daughter as one full of life and love, she added. "Today I even try to laugh when I think of her and not just always cry."