Today, highly qualified women — and there are more of them than ever — tend to want to work, even if that means forgoing children; by their mid-40s, one in three German women live in childless households, the highest proportion in Europe along with Austria. At the same time, more and more women need to work, either as single mothers or because their partner cannot support a family alone.

Now, said Ms. Schwesig, who is also family minister in Mecklenburg-Vorpommern, a northeastern state, the mothers who stay at home are increasingly those with less education and sometimes an immigrant background, those whose children would, in her view, “benefit the most from visiting a childcare facility all day.”

In late 2001, an O.E.C.D. study of literacy skills of 15-year-olds stunned Germany by ranking it 21st out of 27 and among the last in terms of social mobility, even though it has Europe’s largest economy. Two years later, the government, Social Democratic at the time, made available €4 billion, or $5.7 billion, to introduce all-day programs at 10,000 schools by 2009. In the end, some 7,200 schools took part, joining a small existing stock.

Intentionally or not, the mostly male establishment unleashed a long-incipient power: mothers chafing to work who needed longer school hours.

In the rectory next to Neuötting’s 15th-century St. Nicolas Roman Catholic Church, the priest, Florian Wöss, reluctantly accepts the change. His parish runs two kindergartens for children over 3. More mothers have asked him to accept younger children. “I don’t like the fact that more mothers feel they have to hand over their children and go to work,” he said. “But it is a reality.”

Local clergy debated whether to stall the trend by simply refusing, he said. “We came to the conclusion that the pressure is so overwhelming and so multilayered that we can’t stop it.”

Wolfgang Gruber of the Bavarian education authority concurs. He uses words like “flood” and “avalanche” to describe the demand for afternoon schooling. From 2006 to 2009, only 40 primary schools in Bavaria converted. This school year, the number of all-day programs shot to 150. The aim is to introduce afternoon classes in 540 of the 2,300 primary schools, Mr. Gruber said.