Worried about their students, some St. Paul school staffers recently asked the public to donate winter coats for kids. Within a few days, they collected and distributed twice the number of coats they requested — all because a school employee said she had seen several children waiting for a bus this winter with only a towel wrapped around them.

Conditions may be even more dire for low-income kids in Ohio, where the Cleveland schools have regular programs to send food home with students for nights and weekends.

Those are just two examples of what school employees here and elsewhere feel they must do to support learning, because a growing share of their students come from low-income families. In fact, according to a new analysis of federal data, for the first time slightly more than half of all American public school kids are eligible for free or reduced-price lunches.

That demographic change raises major questions about the future of public education and the resources needed to support it. School finance formulas include additional state and federal funding for poor kids. But those agreements were struck when lower-income kids were in the minority. What happens as low-income children become the majority nationally? Education practices, policies and financing must adjust to growing numbers of needy families and children.

Statistics on free and subsidized lunch have become measures of poverty, but not all eligible students are among the poorest of the poor. Subsidized lunches are available to students with family incomes of up to $43,568 for a family of four, which is about 185 percent of the federal poverty level.

Even so, there’s no doubt that public schools are educating larger numbers of low-income children, and it’s clear that the trend began before and is continuing after the most recent recession.

Last week, the Southern Education Foundation issued a report that said 51 percent of children in public schools in the United States qualified for free or subsidized lunches in 2013 — the first time in a half-century that lower-income kids made up the majority of students. By comparison, fewer than a third of students nationally qualified in 1989, while 38 percent were eligible in 2000.

According to the new figures, Mississippi had the highest percentage of kids from lower-income families among the states — nearly 3 in 4 — and Minnesota’s rate was 38 percent.

As enrollments shift to majority-poor student populations, certain types of challenges increase. Studies show that more than half of economically disadvantaged kids start kindergarten with dramatically smaller vocabularies and that they are less ready to learn than their peers. Some of the children are less likely to have support at home for their academics, and they are more likely to have bad experiences in school and drop out. And when they miss out on good educations and job training, they can become locked in the cycle of poverty as adults and parents.

Higher numbers of low-income students reflect the growing income inequality that’s fueling local and national discussions. In his State of the Union address, President Obama outlined proposals to narrow those disparities through expanded preschool, free community college, an increased minimum wage and various tax credits to improve family incomes.

During a forum last week in Washington, D.C., Minneapolis Mayor Betsy Hodges told a national group that addressing income equity is key to her city’s growth. It’s important to support programs that improve learning for students, she said, but it’s also critical that parents of lower-income youngsters have opportunities for living-wage jobs.

Putting more people to work in better jobs would improve economic stability, rebuild the middle class, and reduce the number of students from homes where coats and food are in short supply.