Most charter schools in the Twin Cities still underperform academically when compared with traditional public schools and are highly segregated by race and income, according to updated research released Friday by the University of Minnesota.

The new data, collected in 2010-11 and augmenting a 2008 study by the U's Institute on Race and Poverty, shows that charter school enrollment growth has slowed but little else has changed in the three years since the original study was released.

"Despite some significant changes in the state's charter laws aimed at improving accountability ... charter schools as a group continue to fail to meet the academic and social objectives set forth by proponents," Myron Orfield, director of the Institute on Race and Poverty, said in a statement.

The results drew a quick and extensive rebuttal from Eugene Piccolo, executive director of the Minnesota Charter School Association. Piccolo said the study failed on several fronts, including a failure to note that many families who send their children to charter schools with a limited racial mix are doing so freely.

"It seems that there is an agenda [by the institute] ... they seem to want to go back to busing and other things going on 40 years ago," Piccolo said.

According to the institute's latest research:

A high proportion of charters are essentially single-race schools. In sharp contrast with the traditional system, where the percentage of schools that are integrated has increased steadily, the share of integrated charter schools has been stagnant.

As a result, charter school students of all races are still much more likely to be attending segregated schools than their counterparts in traditional schools, and the gaps are widening.

In 2010-11, 89 percent of black charter students attended segregated schools, up from 81 percent in 2000-01. By comparison, 44 percent of black students in traditional public schools in the metro were in segregated settings, down from 56 percent in 2000-01.

Hispanic, Asian and American Indian charter students were also roughly twice as likely to be in segregated school settings as their traditional school counterparts in 2010-11.

"The high rates of racial and economic segregation matter because research shows that students do worse in segregated school environments than in integrated settings," said Tom Luce, research director of the institute. "Given that, it's not surprising that this work, along with virtually every other comprehensive study of charter schools in Minnesota, shows that charter schools are outperformed by their traditional counterparts in standardized testing, even after controlling for school characteristics such as poverty."

The institute's analysis of 2010-11 test score data shows that charters as a group still lag behind traditional schools. Proficiency rates are 7.5 percentage points lower for math and 4.4 points lower for reading in charter elementary schools than in traditional elementary schools.

"The problems are not only with the academic and social performance of charter schools," Orfield added. "Some charter schools have also been managed very badly."

The study found that four charter school closures resulted from illegal mishandling of money and seven others involved financial mismanagement.

Study strongly challenged

Along with challenging the study's findings on racial mix, Piccolo also contended that the study "pooh-poohs" charter schools that are achieving with a high portion of their students living in poverty. He pointed to Harvest Preparatory School in Minneapolis as an example.

He said the study also doesn't account for charter schools that have many students who are academically challenged because English is their second language.

As for schools being shut down, he said: "If schools aren't performing, they will close. What government program can be named that if it doesn't work, it is closed down? There are none, even in public schools."

Paul Walsh • 612-673-4482