May 7, 2008
Chicago's multi-grade charter high schools (those serving students in grades 7-12, 6-12 or K-12) appear to improve their students' chances of graduating and attending college, as compared with the city's traditional public high schools, according to a RAND Corporation study issued today.
The study is the first to rigorously examine the impacts of charter schools on the critical measures of high school graduation and college entry.
The study finds evidence that Chicago's charter high schools may produce positive effects on ACT scores, the probability of graduating, and the probability of enrolling in college—but these positive effects are solidly evident only in the charter high schools that also included middle school grades. For the average eighth-grade charter student in Chicago, continuing in a charter high school is estimated to lead to
- an advantage of approximately half a point in composite ACT score (for which the median score for the students included in the analysis is 16)
- an advantage of 7 percentage points in the probability of graduating from high school
- an advantage of 11 percentage points in the likelihood of enrolling in college.
“The results for the charter high schools are encouraging and raise questions as to why students attending these schools exhibit higher graduation and college attendance rates,” said Ron Zimmer, co-author of the study and a senior policy researcher at RAND, a nonprofit research organization. “If the educational community is to learn from charter schools, we need to explore further the factors that lead to these results.”
Charter schools are publicly funded schools that operate outside direct school district control and are intended to provide educational choice to families, reduce bureaucratic constraints on educators and provide competitive pressure to conventional public schools.
Forty states and the District of Columbia have charter-school laws, and more than 4,000 charter schools operate in the United States, enrolling more than 1 million students.
“The strongly positive attainment results for Chicago's multi-grade charter high schools suggest that test scores alone may not fully measure the benefits of charter schools for their students,” said Brian Gill, a study co-author and a senior social scientist at Mathematica Policy Research, Inc.
The authors contend that additional research is needed before it can be determined how charter high schools produced these results and whether district-run schools can produce positive effects by incorporating middle school and, perhaps, elementary grades onto the same campus.
The study also found that in grades K-8, Chicago charter schools are doing about as well as the city's traditional public schools in raising student achievement as measured by test score, but that charters do not do well in test score achievement during their first year of operation. On average, the prior achievement levels of students transferring to charter schools differ only slightly from the citywide average and from the achievement levels of peers in the district-managed Chicago public schools they departed.
In addition, charter schools in Chicago are not having major effects on the sorting of students by race, ethnicity or achievement and while charter schools have been criticized for “skimming the cream” by attracting the top public school students, this was not the case in Chicago.
The study includes data from the 1997-98 through 2006-07 school years, except for graduation and college attainment data, which included 1997-98 through 2005-06.
The full report, “Achievement and Attainment in Chicago Charter Schools,” and a report summary are available at www.rand.org.
The report was conducted as a collaboration between RAND Education, Mathematica Policy Research, Inc., and Florida State University. Support was provided by the Bill and Melinda Gates Foundation, the Joyce Foundation, the Stranahan Foundation and the William Penn Foundation.
RAND Education, a division of the RAND Corporation, is a leader in providing objective, reliable research and analysis on educational challenges that is used to improve educational access, quality and outcomes in the United States and throughout the world.
Mathematica (www.mathematica-mpr.com), a nonpartisan firm, conducts policy research and surveys for federal and state governments, foundations, and private-sector clients. The employee-owned company, with offices in Princeton, N.J., Washington, D.C., Cambridge, Mass., and Ann Arbor, Mich., has conducted some of the most important studies of education, disability, health care, early childhood policies, welfare, employment, and nutrition programs in the U.S. Mathematica strives to improve public well-being by bringing the highest standards of quality, objectivity, and excellence to bear on the provision of information collection and analysis to its clients.