Students at charter schools in Indianapolis achieved twice as much growth in reading and math test scores as similar students at Indianapolis’ traditional public schools, according to a new study from Stanford University.
Growth was especially strong among African-American students. But interestingly, Hispanic and low-income students did slightly better at traditional public schools than at Indianapolis’ charter schools.
Those results were part of a national analysis of charter school students in 41 urban centers, conducted by Stanford’s Center for Research on Education Outcomes, or CREDO.
Indianapolis was one of 26 cities where charter school students outperformed their peers at traditional public schools. In 11 cities, charter school students lagged their traditional public peers. And in four cities the results were no different.
The gains of charter school students over their traditional public school peers were not as dramatic in Indianapolis as in Boston, Washington, D.C., Memphis, Nashville, New Orleans, Newark and the San Francisco areas. But Indianapolis was roughly equal to or better than all other cities in the study.
Indianapolis is also among the cities where charter school students are making large enough gains each year that, if they remain enrolled in charter schools, they would catch up to the state averages for reading and math, according to the Stanford researchers.
"This research shows that many urban charter schools are providing superior academic learning for their students, in many cases quite dramatically better,” said Margaret Raymond, the Stanford researcher who led the study, in a prepared statement. “These findings offer important examples of school organization and operation that can serve as models to other schools, including both public charter schools and traditional public schools."
The Stanford research is widely respected because it is based on the nation’s largest database of records for individual students. The Stanford researchers compared each charter school student’s reading and math test scores each year to a “virtual” peer at a traditional public school.
These virtual peers were created by averaging the scores of as many as seven traditional public school students who shared the key demographic, income and geographic traits of the charter school student they were compared against.
The study included students who were enrolled in charter schools in any of the school years from 2007 to 2011. Students who remained enrolled in charter schools for more years saw increasingly larger gains over their traditional public school peers.
For example, charter school students in Indianapolis that spent four years in a charter school had, by the end of that period, grown their math and reading abilities by about half a school year more than their traditional public school.
“These charter sectors appear to provide their students with strong enough annual growth in both math and reading that continuous enrollment in an average charter school can erase the typical deficit seen among students in their region,” the Stanford researchers wrote in their study.
The Stanford study reports differences in learning gains in standard deviations from an average. For nationwide results, researchers at Stanford have done research to convert those statistical differences into days of learning gained or loss.
This conversion is based on nationwide results on the National Assessment for Educational Progress, a standardized test that produces something called the Nation’s Report Card. But local results on the NAEP test often vary from the national average, so the Stanford researchers did not apply the conversion to local results.
If Indianapolis NAEP results did track with the national average, then local charter schools would have grown 50 days more in reading and 43 days more in math, each year.
The growth gains were largest for African-American students and students whose first language isn’t English.
African-American students in charter schools progressed as quickly in reading as white students in traditional public schools. But in traditional public schools, African-American students fell behind their white peers by about 43 days each year.
In math, African-American students fell behind white students at traditional public schools by about 21 days per year in charter schools but by 79 days per year in traditional public schools.
African-American students in poverty fell behind white students at an even faster rate than did black students in poverty attending charter schools.
Hispanic students in Indianapolis’ traditional public schools slightly outperformed Hispanic students in charters schools, in both reading and math.
Also, low-income students—those eligible for free and reduced-price lunches—did slightly better at Indianapolis’ traditional public schools than at charter schools.
One exception was Hispanic students in poverty at charter schools: They grew slightly faster in math than their counterparts at traditional public schools. Reading growth was the same for Hispanic students in poverty at both types of school.
Students still learning English fell behind native English speakers at all schools—but the gap in learning was half as large, in both reading and math, at charter schools than at traditional public schools.
Charter schools in Indianapolis were a mixed bag for white students, who grew faster in reading but slower in math than white students in traditional public schools.