Along with tens of thousands of young people from around the world, she decorated one of 1,000 giant dominoes erected along the strip that once divided East and West Germany and then toppled to commemorate the end of the cold war.
"I knew everything already, how the border was," says Marlene, a 9th-grader who lives in Berlin's Prenzlauer Berg, not far from where the wall was. "The parents in half the class had something to do with it." She knew that her mother had been barred from taking her high school exam because of her parents' church activities. She knew, too, that her friend's grandfather was put in jail when he tried to escape, only to be denounced by a friend. [Editor's note: The original misstated how her mother left East Germany.]
"It's something everybody should know about so we can treasure what we have," says Marlene, who attends Berlin's Schliemann-Gymnasium. "So that if it happens again, we know what to do."
In the Black Forest village of Ichenheim, near the French border, Tobias Geiser knew little of his country's eastern half until his teacher sent him on a historical scavenger hunt. After months of interviews, he and fellow students built a Trivial Pursuit of sorts about the German Democratic Republic's (GDR) history.
His verdict? "The wall still exists in people's heads," says Tobias, whose project won third place in a national history competition "We hope that that can happen if the economy in the east improves."
Study: Kids have rosy view of east
Last year, a study stunned Germans by revealing not only how little youths know of the GDR, but how many still view it as a cozy, socially just society. Two decades after unification, children's views of their country's second dictatorship still hinges on whether they grew up in the east or in the west.
Conducted with 5,219 schoolchildren in Berlin, Brandenburg, Bavaria, and North Rhine Westphalia, Ms. Deutz-Schroeder's survey showed the disparities: Only 57 percent of young people from East Germany approved of the Federal Republic's political system as opposed to 83 percent from West Germany.
Worrisome to many, for example, was that 66 percent of the 16- and 17-year-olds in the state of North Rhine-Westphalia didn't consider the GDR a dictatorship; fewer than two-thirds of East German pupils thought the economic system worked better in the west than in the GDR. [Editor's note: Original did not include the state.]
The findings acted as a catalyst for change, setting up a small revolution that culminated with hundreds of school projects like the one Marlene and Tobias were involved in.
"One wants the wounds that came with the unification process to heal, and the school projects are an important step to do that," says Johannes Moser, a professor at Munich's Ludwig Maximilian University, who was a juror in a nationwide competition that rewarded the best wall-related school project. "They have an important multiplier effect," says Mr. Moser.
History minus the ideology
Experts tend to agree that too little time is devoted to teaching GDR history – but note that it typically takes two decades for history to be absorbed and taught without ideological twists.
"Until the wall came down, there was no GDR history that wasn't ideologically tainted," Professor Moser says. "We need teaching materials."
But, he notes, "a lot has happened in the last 20 years," with increasing focus on different perspectives .
"That young people don't know when the wall was built, or who [GDR leader] Erich Honecker was isn't what matters," says Henning Schluss, an education expert at Berlin's Humboldt University who has developed a core curriculum on GDR history. "What matters is to develop an interest in, a taste for history – what a dictatorship, what democracy, means, how democracy can be threatened."
That, he says, is happening.
But the challenges are many. In Frankfurt, 11th-grader Kira Orth would like to know more about GDR history –but there's not enough space in the curriculum. Beyond that, former GDR teachers have struggled with what they present to children.
"To talk about how they, as history teachers, had to teach 20 years ago, isn't easy, it makes teachers vulnerable," says Mr. Schluss. "How can they expected to have a critical image of the GDR when they don't have it themselves?"
Gabriele Flegel, a Berlin teacher who helped Marlene Muehlmann participate in the Berlin domino project and who was a history teacher in the east before the wall came down, says that adjusting to teaching in a united Germany took time. But Ms. Flegel has what many pupils won't have in the future: firsthand knowledge.
Need to hear from eyewitnesses
Many Germans want the country to draw more on the experience of those who lived through the wall's decades.
"They don't use the chance enough. The eyewitnesses are here, the places are here," says Anke Burmeister of Berlin, the mother of a 9th-grader who participated in the domino project. She fled eastern Germany through Hungary a few months before the wall came down. "The generation of my children is the first for whom it won't play a role."
In the Baden Wuerttenberg town of Trossingen, in southern Germany, 12th-grader Franziska Muehlbauer found that her project helped erase stereotypes. "The GDR isn't a theme at home," Franziska says. 'Until now, I noticed how people made fun of about the people from the east, because they talk differently."
The anniversary celebrations and the school projects are important, says Schluss, because "eastern Germans notice that their history is valued, that it's not just a footnote in history. It's helping people develop a positive relationship to German history."
And, he adds, "only if Germany looks at itself as one country can it participate in a bigger European project."
Special report: When the Berlin Wall came down