This new WEAC Research Brief concludes that there is little evidence to substantiate the expansion of private voucher schools on the grounds that they are intended to help student achievement: “Research in Wisconsin and other states consistently shows little to no voucher school advantage, and in fact often documents significant ill-effects on students including: school closings, high rates of student attrition for lower-performing students, and decreased assessment scores in math and reading.”
WEAC Research Brief
School voucher proponents long maintained that the dynamic of consumer preference in education would result in improved student outcomes. Yet after 25 years of voucher schools in Milwaukee, claims of increased student success are difficult to find. Since its inception in 1990, the Milwaukee program expanded to include religious schools, students already attending private schools, and families with higher incomes than originally established for the program. Today, after more than $1 billion in funding, the Milwaukee voucher program stands as the state’s second largest system, and, recently, vouchers were expanded statewide.
A number of studies examined voucher schools here and nationally as well. One of the most significant findings about the Milwaukee voucher program to date is that 41 percent of voucher schools failed since the program’s inception. Start-ups and unaffiliated voucher schools were the most likely to falter. The voucher program includes some well-established religious schools, but many fly-by-night operations were allowed to participate.
Failed voucher schools include ones that stole tax dollars, closed mid-year, and refused to pay staff or provide textbooks for students. Millions in tax dollars were wasted on schools that no longer exist. The academic effects of these school failures on thousands of participating students have not been measured.
Evidence from Milwaukee does not show improved student success
Where voucher schools are operating, evidence does not support the assertion that voucher mechanisms improve student achievement. Voucher supporters funded a comprehensive five-year study of the Milwaukee Parental Choice Program (MPCP) by the School Choice Demonstration Project. In the end, the researchers concluded:
“No report . . . has found major differences in achievement test scores between MPCP students and similar MPS [Milwaukee Public Schools] students. The results . . . do not support a comprehensive conclusion that the MPCP necessarily provides a better learning environment than MPS.”
Peer-reviewed studies of the Milwaukee program later found evidence that lower- performing students left voucher schools in disproportionate numbers, and that schools with higher percentages of voucher students were more likely to lose students than other private schools in the program. Another important finding was that children who left voucher schools experienced significant gains when they returned to public schools.
“In general, all students who transfer to the public sector realize significant achievement gains after doing so, although these gains are estimated to be larger for low-performing students than for their higher achieving peers.”
“. . . Former voucher students exhibit significant achievement increases in both reading and math after they transfer to the public schools. . . . In most cases, the magnitude of these estimates is substantial, comparing favorably to the effects of several well-known interventions, such as class size reduction.”
Proponents often assert that voucher students graduate at higher rates than public school students. The School Choice Demonstration Project analyzed graduation rates between matched groups of students in the MPCP and MPS. The finding, however, was based on just a partial sample of the original 9th grade MPCP cohort because information for remaining students could not be found, leading one reviewer to state:
Roughly 56% of the original sample of 801 MPCP 9th graders were not still enrolled in a MPCP high school in 12th grade. The inferences drawn about the effects of the MPCP on graduation rates compared with those in the MPS are severely clouded by substantial sample attrition.
Assessing their own findings, the authors conceded: “These rates are calculated excluding unknowns from the denominator,” and that “If unknowns were to be included, the rates would obviously be lower.” About their results, the researchers ultimately concluded:
Ninth grade students who were in the MPCP in 2006-07 were more likely to graduate high school in 2009-10 than similar 9th grade students who were in MPS in 2006-07 . . . but the effects were not statistically significant.
The strongest finding about graduation was that children who stayed in MPS for all four years, or children who stayed in the MPCP all four years, “were far more likely to graduate and enroll in college” than other students.
Students who moved from one school to another, in other words, were less likely to attend higher education than non-moving peers—a finding which contradicts the very premise of choice that enhanced student mobility will improve educational outcomes.
Evidence from other states
A number of recent voucher studies in other states documented actual loss in academic achievement for participating students.
In Indiana, researchers found that “voucher students who transfer to private schools experienced significant losses in achievement” in mathematics, and also saw no improvement in reading.
A comprehensive study of vouchers in Louisiana found “large negative results in both reading and math. Public elementary school students who started at the 50th percentile in math and then used a voucher to transfer to a private school dropped to the 26th percentile in a single year.”
Martin West, professor at the Harvard Graduate School of Education, called the negative effects in Louisiana “as large as any I’ve seen in the literature — not just compared with other voucher studies, but in the history of American education research.”
In Ohio, the Thomas B. Fordham Institute, a conservative think tank and proponent of school choice, released a study of that state’s program which found: “Students who use vouchers to attend private schools have fared worse academically compared to their closely matched peers attending public schools.”
In a major review of literature on voucher programs nationally, professor of education at Stanford University, Martin Carnoy, summarized:
“In the few cases in which test scores increased, other factors, namely increased public accountability, not private school competition, seem to be more likely drivers. And high rates of attrition from private schools among voucher users in several studies raises concerns. The second largest and longest-standing U.S. voucher program, in Milwaukee, offers no solid evidence of student gains in either private or public schools.”
“In the only area in which there is evidence of small improvements in voucher schools — in high school graduation and college enrollment rates — there are no data to show whether the gains are the result of schools shedding lower-performing students or engaging in positive practices.”
Research in Wisconsin and other states consistently shows little to no voucher school advantage, and in fact often documents significant ill-effects on students including: school closings, high rates of student attrition for lower-performing students, and decreased assessment scores in math and reading. There is little evidence to substantiate the expansion of private voucher schools on the grounds that they are intended to help student achievement.
In fact, the larger idea that private schools are better than public schools in promoting academic achievement is open to significant debate. Researchers from the University of Illinois Champaign-Urbana found public schools actually outperform private ones when comparisons control for student demographics.
Simple ranked comparisons of test scores show that private schools overall (not specific to voucher schools) outscore public schools, but to be meaningful comparisons must account for student differences, including the number of low-income students and those with special needs. Using results from the National Assessment of Educational Progress and the Early Childhood Longitudinal Study, the researchers concluded:
When controlling for demographic factors, public schools are doing a better job academically than private schools. It seems that private school students have higher scores because they come from more affluent backgrounds, not because the schools they attend are better educational institutions.
More recent studies from the Educational Testing Service, Notre Dame, and Stanford looked at the same data sets and came to similar conclusions. The authors posit that a stolid private school curriculum, varied teacher quality, and lack of professional development in current pedagogical techniques may account for the fact that private schools do not fare as well as public ones in helping students from different backgrounds. In other words, evolutions in curriculum and practice may well contribute to the advantages that public schools provide students.
 Michael R. Ford and Fredrik O. Andersson, “Determinants of Organizational Failure in the Milwaukee School Voucher Program,” Policy Studies Journal, May 2016.
 School Choice Demonstration Project, “Student Attainment and the Milwaukee Parental Choice Program: Final Follow-up Analysis,” University of Arkansas, February 2012, p. 17.
 Deven Carlson, Joshua M. Cowen and David J. Fleming, “Life After Vouchers: What Happens to Students Who Leave Private Schools for the Traditional Public Sector?” Educational Evaluation and Policy Analysis (June 2013), p.193
 Carlson, Cowen and Fleming, “Life After Vouchers: What Happens to Students Who Leave Private Schools for the Traditional Public Sector?” p. 189.
 Casey Cobb, “Review of SCDP Milwaukee Evaluation Report #30,” National Education Policy Center, April 2012.
 School Choice Demonstration Project. “Student Attainment and the Milwaukee Parental Choice Program,” March 2011, pp. 6, i.
 School Choice Demonstration Project. “Student Attainment and the Milwaukee Parental Choice Program,” March 2011, p. i.
 Kevin Carey, “Dismal Voucher Results Surprise Researchers,” New York Times, 2/23/2017.
 Education Research Alliance. “How has the Louisiana Scholarship Program Affected Students?” February 22, 2016; in Carey, Kevin. “Dismal Voucher Results Surprise Researchers,” New York Times, 2/23/2017.
 Carey, Kevin. “Dismal Voucher Results Surprise Researchers,” New York Times, 2/23/2017.
 Thomas B Fordham Institute. “Evaluation of Ohio’s EdChoice Program,” July 2016; in Carey, Kevin. “Dismal Voucher Results Surprise Researchers,” New York Times, 2/23/2017.
 Martin Carnoy. “School vouchers are not a proven strategy for improving student achievement,” Economic Policy Institute, February 28, 2017.
 Julia Ryan, “Are Private Schools worth it?” The Atlantic, October 18, 2013; Christopher Lubienski and Sarah Theule Lubienski. The Public School Advantage: Why Public Schools Outperform Private Ones, University of Chicago Press, 2013.