For years, Germany's selective college-prep "gymnasiums" produced the worlds' Einsteins and Göthes and its trade-oriented Hauptschule turned out the most reliable – and best paid – artisans. Tracking pupils by skill level as early as age 9 worked. So did relying on mothers staying home, with child care for young children almost nonexistent, kindergarten optional, and school ending before lunch.
But as Germany has become more heterogeneous, children born to less-privileged, working parents and non-native residents have started falling through the cracks.
Today the Hauptschule is often seen as a dumping ground offering graduates little hope of a job, and the gymnasium as reserved for the elite. Studies by the Organization for Economic Cooperation and Development (OECD) have said that in no other country is the academic success of children so dependent on their parents' socioeconomic backgrounds.
The debate became more urgent after researchers asked schoolchildren how they perceived their lives. In the recently released results of the study, children stunned Germany by showing how conscious they are that their social backgrounds stick to them like glue, charting their future.
"I'm in the Hauptschule, so I know I won't be able to do much when I'm older," said Kevin, one of a dozen children interviewed extensively by researchers. With his mother working as a cook's helper, he is on his own after school and hangs out with friends or watches television.
Conversely, Monique, who lives in a residential area near Munich and attends the selective gymnasium, sees her future with confidence: "I hope to have a good job," she said. In the afternoon, Monique goes from dance to music lessons, with her mother coordinating her free time.
"The most stunning revelation about this study is how early and intensely children grasp where they belong and what their perspectives are," says Klaus Hurrelmann of Bielefeld University, who conducted the study.
Sponsored by the nonprofit children's association World Vision in Friedrichsdorf, Dr. Hurrelmann's team of researchers interviewed 1,600 children, ages 6 through 11, and their parents, focusing in particular on 12 children representing different social groups.
German children's social baggage weighs heavily on them, according to the World Vision study, which came out last fall.
While 82 percent of children from upper-class backgrounds say that they plan to take the prestigious Abitur, the high school exam that opens the door to studying at a university, only 20 percent of children from lower-income families do.
Like Kevin, children from less-privileged backgrounds are less likely to attend afternoon activities such as dancing and music or to belong to clubs. Three-quarters of the low-income parents interviewed said that they aren't in a position to organize afternoon activities for their children, because both parents are employed.
And yet the study makes it clear: Those children lose out when they don't participate in the music classes, sports clubs, and other opportunities their wealthier peers enjoy.
"The study shows how important it is to offer parents institutional support – more child-care options, all-day school – because parents have limits," says Hurrelmann. "That we see that through the eyes of the children gives a new accent to the entire discussion, one that is devoid of ideology."
"That it came from children themselves was an eye-opener," said Miriam Gruss of the Liberal Party, who chairs the children's commission in Germany's parliament.
Like Ms. Gruss, politicians and experts say that the study gives new weight to calls for Germany to move away from its traditional "mothers-do-it-all" culture and develop a better infrastructure to help families of all income levels take care of their children.
Germany's mistrust of public child-care services has deep roots. It is, in part, a reaction to the situation in former East Germany, where most mothers worked and left their children in child care.
Over the years, while neighboring countries such as France and Sweden developed infrastructure to help women work, West Germany encouraged mothers to stay home. Today, more than in most industrial nations, the lack of child-care options is one reason why German women tend to choose between work and family.
"The choice between family and career is a difficult one," says Christian Alt, a researcher for the German Youth Institute in Munich. "When you make the choice even more difficult, you have what we've had over the past 15 years: Birthrates go down."
Germany's 1.3 children per woman compares with 1.9 in France and 1.8 in Sweden. The birthrate among high-ranking professional women is particularly low. Fearing that sinking demographics could sap the workforce and undermine the state pension system, politicians have reacted.
Some states, such as Hamburg, are calling for "schools for all," where pupils stay together for nine or 10 years. Berlin has raised the decisive point of deciding the course of future schooling to age 11 or 12.
To improve the opportunities for low-income children, the state of Hesse is considering all-day schools and increasing the number of schools offering lunch and afternoon classes or activities.
Perhaps the greatest symbol for change is Ursula von der Leyen, who's Federal Minister for Family Affairs, Senior Citizens, Women and Youth and the mother of seven. Shaking her conservative party's image of stay-at-home mothers, she has made efforts to combine family and job a hallmark of her tenure. By 2013, for example, Dr. von der Leyen wants to triple the number of nurseries for toddlers to 750,000.
The publicity surrounding the World Vision study testifies to a historic breakthrough in German society's view of caring for children, says Dr. Alt.
"Society's view in the past was that mothers were the only link to children. What we knew about children came from the mother," says Alt. "But [now we see] that children have their own perspective, that they have a message, and that their opinions are reaching political circles. That is totally new."
As a result of the study, Alt notes, "Politicians say, 'We have to think about whether we want to have children-friendly cities, and to do that, we have to relieve families.' "