Friday, March 20, 2009

Charter School: No Skimming, No Rising Tide, No Better or Worse

"...charter-school competition is
unlikely to create arising tide of school performance,
in the absence of dramatic changes in the structures,
incentives, culture, and operation of conventional school districts."

A timely new study from RAND on charter schools provides analysis of several key questions in eight states.

Charter Schools in Eight States:
Effects on Achievement, Attainment,
Integration, and Competition

Charter schools are publicly funded schools that operate outside the direct control of local school districts, under a publicly issued charter that gives them greater autonomy than other public schools have over curriculum, instruction, and operations. Their students (or the students’ parents) choose to attend the charter schools rather than being assigned to a school based on residential location. The first U.S. charter school opened in 1992, and the scale of the charter movement has since grown to 4,000 schools and more than a million students in 40 states and the District of Columbia. With this growth has also come a contentious debate. Supporters argue that charter schools can improve student achievement and attainment, serve as laboratories for innovation, provide choice to families that have few options, and promote healthy competition with traditional public schools (TPSs).

Critics worry that charter schools perform no better (and, too often, worse) than TPSs, that they may exacerbate stratification by race and ability, and that they harm the students left in TPSs by skimming away financial resources and motivated families.

In recent years, research has begun to inform this debate, but many of the key outcomes have not been adequately examined or have been examined in only a few states. Moreover, questions about the validity of the findings of even the best-designed charter-school impact studies have remained, producing deep uncertainty about the interpretation of results.

What Are the Characteristics of Students Transferring to Charter Schools?
  • We find no systematic evidence to support the fear that charter schools are skimming off the highest-achieving students.
  • Transfers to charter schools did not create dramatic shifts in the sorting of students by race or ethnicity in any of the sites included in the study.
  • We find suggestive evidence that African American students are more likely to self-segregate: African American students transferring to charter schools moved to schools with higher concentrations of African American students in five of seven locales.
What Effect Do Charter Schools Have on Test-Score Gains for Students Who Transfer Between Traditional Public Schools and Charter Schools?
  • The average effect that charter schools are having on their students across grades K–12 is difficult to estimate.
  • In five out of seven locales, these nonprimary charter schools are producing achievement gains that are, on average, neither substantially better nor substantially worse than those of local TPSs.
  • In Chicago (in reading) and in Texas (in both reading and math), charter middle schools appear to be falling short of traditional public middle schools.
  • In most locations, charter schools have difficulty raising student achievement in their first year of operation, typically producing achievement results that fall short of those of local TPSs. This is consistent with prior research and common sense and may not be a charter specific phenomenon: Opening a new school is challenging, regardless of whether the school is a charter school. Across locations, we see a general pattern of improved performance as schools age.
  • Charter schools in most locales have marginally greater variation in performance than TPSs, as measured by the achievementimpact estimate for each school, and, in some locations, this may simply reflect greater measurement error associated with the smaller
    average size of charter schools. Ohio is a notable exception: Its charter schools have a much wider range of variation in performance than its TPSs have.
What Is the Effect of Attending a Charter High School on the Probability of Graduating and of Entering College?
  • In the two locations with attainment data (Florida and Chicago), attending a charter high school is associated with statistically significant and substantial increases in the probability of graduating and of enrolling in college.

What Effect Does the Introduction of Charter Schools Have on Test Scores of Students in Nearby Traditional Public Schools?

  • There is no evidence in any of the locations that charter schools are negatively affecting the achievement of students in nearby TPSs. But there is also little evidence of a positive competitive impact on nearby TPSs.

What Are the Policy Implications?

  • We emphasize the modifier “possible” in discussing policy influences: ...conclusions must remain tentative.
  • Findings on the students transferring to charter schools and on the integration effects are largely consistent across sites, suggesting that policymakers need have little fear of cream-skimming or of substantial increases in racial isolation.
  • The overall estimates of the average achievement impacts of charter schools can provide little guidance for policy, given that the validity of the estimates for elementary schools is in doubt.
  • the challenge is to minimize the
    number of charter failures without sacrificing successful charter
    schools.
  • The absence of evidence of substantial effects of charter schools on the achievement of students in nearby TPSs might be encouraging to policymakers who were concerned about negative effects and disappointing to policymakers who hoped that competition would induce TPSs to improve.
  • Our findings support the hypothesis (see, e.g., F. Hess, 1999) that charter-school competition is unlikely to create a rising tide of school performance, in the absence of dramatic changes in the structures, incentives, culture, and operation of conventional
    school districts.

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