Charters are often accused of taking the brightest, most motivated or more privileged students from traditional public schools. However, there is research evidence to the contrary showing incoming charter school students are just as diverse (racially and economically) as non-charter students and often lower performing.
Sometimes this argument takes another form, with charter school detractors saying that charter schools "push out" struggling students. The authors of an analysis published in Educational Evaluation and Policy Analysis, September 4, 2013, examined exit patterns of an anonymous urban school district at both the aggregate and individual school levels. After running a wide variety of tests that utilize various measures of "low achieving," the authors found "no empirical evidence to support the notion of push-out. Read the full study.
Charter schools serve equally diverse and low-income students
The National Charter School Research Project (NCSRP), an initiative of the Center for Reinventing Public Education, annually assesses the national charter school movement in a report titled "Hopes, Fears, & Reality: A balanced look at American charter schools." In their 2009 report, they discussed trends from 2005 to 2009 and found that charter schools serve a larger proportion of students of color (61% for charters vs. 47% for non-charters) and low-income students (49% for charters vs. 45% for non-charters) than all traditional public schools. When examining schools within districts, they found student demographics to be the same: 61% students of color in charters versus 60% in their district counterparts; 47% charter free/reduced-price lunch participation versus 45% for non-charters.
Specific to California, EdSource conducts an annual analysis titled "Charter schools in California: Issues and Performance." In 2009, this report found that California charter schools serve more low-income students in high school, and about equal percentages of Hispanic/Latino students and more African American students across grade levels (elementary, middle and high school). When controlling for student demographics, this report found that charters fostered higher academic results in API growth and English in high schools, and API growth, English and math in middle schools. Charter schools run by Charter Management Organizations (CMOs) earned higher results across all subjects and grade levels.
Charter schools educate a diverse range of student aptitudes
The RAND Corporation's study (Zimmer et al., 2009) evaluated whether charter schools are "skimming" the best students from traditional public schools in their report, "Charter schools in eight states: Effects on achievement, attainment, integration, and competition". RAND analyzed the academic achievement and demographic characteristics of students transferring into charter schools and found charter schools generally are not drawing the best students away from traditional public schools. Previous test scores for students transferring into charter schools were near or below the averages for every location in the study. They also found that the racial composition of charter schools was similar to that of the traditional public schools the students previously attended.
Motivation to choose does not explain charter school success
Another 2009 study (Hoxby et al., 2009) utilized a quasi-experimental approach (the gold standard for research on actual students) to control for the effects of parent/student choice, by comparing lottery students. Students who applied to attend a charter, whose entrance was decided by lottery, are compared to students who applied but did not get in; controlling for motivation. This study of New York and Chicago charters found that the racial composition, income level and past academic performance of students lotteried-in and lotteried-out were the same (lotteries are random, controlling for the variation among students). Furthermore, the study found that the students who were lotteried-in had higher state test performance in math and reading as well as greater likelihood of graduating. The researchers concluded that attending a charter school for multiple years can close the achievement gap.
Edwards, B., Crane, E., Barondess, H., and Perry, M. (2009). Charter schools in California: 2009 update on issues and performance. Mountain View, CA: EdSource.
Hoxby, C. M., Murarka, S., and Kang, J. (2009). How New York City's charter schools affect achievement. Cambridge, MA: New York City Charter Schools Evaluation Project (second report in series).
Lake, R. J. (Ed.) (2009). Hopes, fears, & reality: A balanced look at American charter schools in 2009 (4th ed.). Seattle, WA: University of Washington Bothell.
Zimmer, R., Gill, B., Booker, K., Lavertu, S., Sass, T. R., and Witte, J. (2009). Charter schools in eight states: Effects on achievement, attainment, integration, and competition. Santa Monica, CA: RAND Corporation.