A proposed $20 billion school-voucher program from the Trump administration, and Education Secretary Betsy DeVos, a school-choice advocate, may have the most momentum for such a plan in decades. That momentum, critics of market-based education policy worry, may leave three recent voucher-effectiveness studies—from the political left and right—worth little more than spitballs.

Vouchers, which essentially parlay tax money traditionally earmarked for public schools into vouchers that let families opt for certain private schools if they choose, are not new. Free-market extoller Milton Friedman wrote at length about the role of government in education in the 1950s. Friedman said that the government owes its citizens an education but that the government just isn’t the best administrator. “Choice” advocates argue that low test scores bear this out. From the Friedman treatise emerged the voucher concept, used today in small batches and in select areas.

Education experts have fresh data on those voucher programs, and the results, which may be as muddied as the education debate itself, show some programs failing, others pulling C’s and select examples earning top marks. The challenge? Uniform voucher execution and results when applied on a broad basis, wrote education-policy researcher Kevin Carey in a commentary for the New York Times.

“ ‘The results [of school voucher research] are startling — the worst in the history of the field, researchers say.’ ” — Kevin Carey, New America

Here’s an excerpt of findings from the conservative-leaning Thomas B. Fordham Institute, one of the three studies that Carey, who’s with the think tank New America, highlights: The results reported here for Ohio’s EdChoice program—one of the nation’s largest voucher programs—are a mixed bag. The study mirrors important trends that can be seen in other voucher research. The modest, positive competitive effect on public school achievement replicates findings from jurisdictions like Florida, Louisiana, and Milwaukee, findings that also offered evidence that voucher competition improved public school outcomes. These are, of course, encouraging for advocates of competition and choice. Yet this study also extends a recent (and, to us, unwelcome) trend that finds negative effects for voucher participants in large statewide programs. While earlier evaluations of privately and publicly funded scholarship programs—usually administered at the city level—found neutral-to-positive impacts on participants, newer studies of Louisiana’s and Indiana’s statewide programs have uncovered negative results, particularly in math.

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Vouchers and charter schools are often lumped together under the push for “choice,” but the different approaches highlight education-policy nuance. “The new voucher studies stand in marked contrast to research findings that well-regulated charter schools in Massachusetts and elsewhere have a strong, positive impact on test scores. But while vouchers and charters are often grouped under the umbrella of ‘school choice,’ the best charters tend to be nonprofit public schools, open to all and accountable to public authorities. The less ‘private’ school-choice programs are, the better they seem to work,” Carey wrote.

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