by Hailey Heinz
July 1, 2013
The math scores of New Mexico charter school students improved significantly less than the scores of their traditional school counterparts, according to a new national study that tracked average year-over-year gains from 2007 to 2011.
The study found no difference in the reading gains of charter vs. traditional public school students.
The findings were released Tuesday by Stanford University’s Center for Research on Education Outcomes, commonly called CREDO.
The study aims to control for demographic differences between charter and traditional school students. Specifically, researchers assigned each charter student a “virtual twin” student in a nearby traditional school, who is meant to be similar in every way except the choice to attend a charter. The “twin” is similar in ways like initial test scores, ethnicity and whether the student is low-income.
The progress of each charter student is then compared to the progress of his or her “twin.”
Researchers found New Mexico students’ reading progress was unaffected by charter schools. But in math, they found traditional school students gained the equivalent of 29 more days of learning than their charter school peers. According to the report, the days of learning are estimates based on statistical findings.
The report also examined the initial test scores of students who transfer to charter schools. Nationwide, the report found charter students had starting test scores below their statewide averages. But in New Mexico, the average charter school student starts with above-average test scores.
Nationally, the study found good news for charters, especially when compared to CREDO’s last study, released in 2009. That study found charter school students nationally underperformed traditional public school students. The latest study found charters nationally had improved to match traditional schools in math scores, and surpassed them in reading.
Bruce Hegwer, executive director of the New Mexico Coalition for Charter Schools, said New Mexico charters have also seen growth since the 2009 report. Specifically, the 2009 report showed New Mexico charters underperforming in both math and reading.
Hegwer, who had just received the 104-page report Tuesday, said it will probably give charters some good feedback.
“My initial thoughts are that I think there’s some valuable information in the report, and I think it kind of gives us some things to take a look at,” Hegwer said.
Hegwer also pointed out that some groups have disputed the report’s methodology and data collection practices. For example, the Washington D.C.-based Center for Education Reform, or CER, released a statement saying the report has “multiple shortcomings.”
“No matter how well-intentioned, the CREDO research is not charter school performance gospel,” said CER President Jeanne Allen. “Similar to its failed 2009 effort, this CREDO study is based on stacking mounds of state education department data into an analytical process that is decidedly lacking in rigor.”