Donald Trump’s nominee for the Department of Education, Betsy DeVos, is an advocate of school vouchers. One should not exaggerate how much influence she will have in promoting this cause. The United States Department of Education has little direct authority over K-12 education and it certainly should not be given any more, because education is quintessentially a state and local issue. But any cabinet position is a bully pulpit, and classical liberals should hope she uses it to create a more favorable climate for state and local voucher initiatives.
The conventional argument for vouchers, itself classically liberal in nature, is that in the long run they are likely to improve human capital, because they will introduce more competition by supplying more private schools for those parents who want to use them. Schools that do better at matching students with the education that is best for them will gain students at the expense of those that do not. Moreover, more competition will lead to more beneficial innovations that will be shared throughout the K-12 educational system. Thus, even if some schools funded by vouchers do not perform well at first, a more competitive system has greater dynamism than a more government controlled system.
While there is much to be said for the human capital argument, yet another classical liberal argument for vouchers is that they promote a free citizenry by creating schools that compete to instill good values and norms in their students.