An increasing number of charter schools that serve mostly white student bodies are opening in racially diverse areas of the Twin Cities, according to a study by Institute of Metropolitan Opportunity, based at the University of Minnesota Law School.

The number of predominantly white charters in the suburbs grew by 40 percent from 2008 to 2013, the study's authors say. As a consequence, they added, those schools are aiding "white flight" from diverse suburban schools in cities such as Bloomington, Apple Valley and Eden Prairie.

"The question is whether charters are the best path available to find ways to better serve low-income students of color, given that the approach has consistently increased segregation in the region's schools, while, at the same time, failing to improve overall student performance," said Myron Orfield, director of the institute.

The institute has been analyzing the racial makeup and academic performance of charter schools since 2008, when it released a study that suggested those schools are highly segregated and fail to provide a quality education.

Tuesday's update to that report makes many of those same assertions. The institute's analysis indicates that charter schools aren't academically performing as well as their traditional public school counterparts, with a handful of exceptions.

Orfield said that local media overhype the accomplishment of those schools in relation to number of charter schools that aren't performing well.

"For every Harvest Prep, there is a LoveWorks," said Orfield, noting the consistently high-achieving Minneapolis charter school and the Golden Valley school that has been cited by the state for employing unlicensed teachers.

Charter school advocates have long maintained that parents should have choices that go beyond traditional public schools. And charter schools, they say, can provide quality educations.

"Parent choice is not segregation," said Eugene Piccolo, executive director of the Minnesota Association of Charter Schools.

Each year, the Star Tribune recognizes schools that have the highest scores on the Minnesota Comprehensive Assessments in relation to their poverty level. This year's list — like others in recent years — was dominated by metro-area charter schools.

The institute, formerly known as the Institute of Race and Poverty, investigates the way laws, policies and practices affect development patterns in U.S. metropolitan regions. It has produced recent studies focused on charter school performance, suburban diversity patterns and the effect of open enrollment on school diversity.

Kim McGuire • 612-673-4469