As the Tennessee General Assembly considers vouchers as part of the education agenda this year, it is important to look at the evidence. That is, do vouchers work? Do voucher programs lead to improved student outcomes. Until now, most research has been mixed, with some suggesting modest gains for students, while some studies showed no significant improvement. These studies focused on older, typically smaller programs.

Now, however, there is data on some statewide voucher efforts. That data suggests, quite strongly, that vouchers don’t work. In fact, the studies indicate vouchers actually cause student achievement to decline.

Kevin Carey writes in the New York Times:

The first results came in late 2015. Researchers examined an Indiana voucher program that had quickly grown to serve tens of thousands of students under Mike Pence, then the state’s governor. “In mathematics,” they found, “voucher students who transfer to private schools experienced significant losses in achievement.” They also saw no improvement in reading.

The next results came a few months later, in February, when researchers published a major study of Louisiana’s voucher program. Students in the program were predominantly black and from low-income families, and they came from public schools that had received poor ratings from the state department of education, based on test scores. For private schools receiving more applicants than they could enroll, the law required that they admit students via lottery, which allowed the researchers to compare lottery winners with those who stayed in public school.

They 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. Results were somewhat better in the second year, but were still well below the starting point.

In June, a third voucher study was released by the Thomas B. Fordham Institute, a conservative think tank and proponent of school choice. The study, which was financed by the pro-voucher Walton Family Foundation, focused on a large voucher program in Ohio. “Students who use vouchers to attend private schools have fared worse academically compared to their closely matched peers attending public schools,” the researchers found. Once again, results were worse in math.

Voucher studies of statewide programs in Ohio, Louisiana, and Indiana all suggest that not only do vouchers not improve student achievement, they in fact cause student performance to decline.

Some state policymakers (State Rep. Bill Dunn, State Senator Brian Kelsey, Governor Bill Haslam) are asking taxpayers to invest in a voucher scheme. These advocates suggest that a voucher program can provide a path to better outcomes for students. However, the results of statewide programs in three different studies indicate just the opposite: Vouchers offer a path to dismal achievement.

Tennessee lawmakers should take a look at the evidence. Vouchers just don’t work. In fact, they harm the very students voucher advocates claim to want to help. Instead of funding voucher schemes we know don’t get results, the state should focus on funding existing programs that will enhance education for all students.

MORE on vouchers:

Vouchers the wrong choice for Tennessee

What Tennessee Can Learn from Louisiana on Vouchers

Fitzhugh on Vouchers

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