Some were surprised by a recent Metropolitan Council study that found more poor people live in Twin Cities suburbs than in the core cities. But that was not news to many suburban school district staffers. During the past 15 years, they’ve seen the numbers of students eligible for free and reduced lunch (one federal measure of poverty) grow significantly.

Schools have had to adjust, and so have other levels of government as they are presented with new challenges. They must re-evaluate how they think about poverty and the services they need to deliver.

The Met Council reported that about 385,000 people live in poverty in the suburbs, compared with about 259,000 in the urban cores. Metro suburbs such as St. Louis Park, Coon Rapids and Shakopee have pockets of concentrated poverty, while other suburban communities such as Richfield and Brooklyn Park have poverty that has become more firmly entrenched.

The shift is significant, because 15 years ago there were no pockets of concentrated poverty outside the core city areas, said Libby Starling, the Met Council’s manager of regional policy and research. Suburban and rural poverty in the seven-country metro area rose by 92 percent from 2000 to 2013, while it grew 24 percent in the two core cities, according to the report, which relied on census data.

Some questioned the Met Council’s conclusions, saying that researchers used a higher income threshold to define poverty than the standard measure. The federal government’s definition of poverty is a family of four with an annual income of $23,834 or less. The Met Council’s statistics are based on families of four with annual incomes less than $44,093. And the council considers poverty concentrated if 40 percent or more of households in a census tract fall below that threshold.

But many federal government programs don’t use that basic standard. Eligibility for inclusion in things like Head Start, school lunch, and housing subsidy programs is based on measures ranging from 130 percent of poverty up to 200 percent.

Starling points out that the results of the study would have been virtually the same with the lower standard. In addition, the council’s conclusions are consistent with national studies and trends.

A book published by the Brookings Institution in 2013 said that between 2000 and 2011, the number of suburban poor in the U.S. grew by 64 percent — more than double the rate in the cities. Granted, context is needed: There are three times as many people living in America’s suburbs, so the overall rate of suburban poverty is still much lower. But the recent rapid increase is significant and has real policy implications.

The authors of the Brookings book suggest the suburbanization of poverty could put a strain on safety-net programs. There are also concerns that some suburbs don’t have the kinds of public transit networks that can connect low-income people to jobs.

Higher levels of suburban poverty and the growing numbers of low-income students reflect the growing income inequality that’s fueling local and national debates on a range of topics. Despite this state’s relative economic strength, as the Met Council study shows, it’s a trend that has serious implications for all Minnesotans.