A new US study has found that vouchers to attend private schools leads to lower student achievement by up to a year or more of learning. It shows that funding disadvantaged students to attend private schools resulted in lower test scores in maths, reading, science and social studies.
The study evaluated the Louisiana Scholarship Program (LSP), which is a voucher plan that provides public funds for disadvantaged students in low performing public schools to attend private schools. It is published in the latest issue of the academic journal Applied Economics
Under the LSP vouchers for students are decided by a lottery if the number of eligible applicants to a private school exceeds the available places. The study compared test results for lottery winners and losers.
The results showed that the vouchers dramatically reduced student test scores. Attending a private school reduced maths scores by an average of 0.41 standard deviations and reduced reading, science, and social studies scores by 0.08, 0.26, and 0.33 after one year. Average student learning in a year is about 0.25-0.33 of a standard deviation, so student outcomes were reduced by over a year of learning in maths and about a year in science and social studies.
The study also found that LSP participation shifts the distribution of scores downward in all four subjects, increasing the likelihood of a failing score by between 24 and 50 per cent. These impacts were similar across family income levels and geographic locations. The effects were more negative in earlier grades, though the vouchers reduced achievement in later grades as well. The effects were similar for Catholic and non-Catholic schools.