I've always been a big fan of school choice, indeed I'd like to entirely abolish the public school system and move to 100% private education. Having public schools makes no more sense than having a public church.
At the same time, I've always been skeptical of arguments that school vouchers could dramatically boost test scores. Indeed I don't even believe that higher test scores are the proper goal of schooling---customer satisfaction is the proper metric. I favor giving people a choice because people generally prefer to have a choice.
I have made two arguments for school vouchers. First, a system of private vouchers can reproduce our current crappy test scores at a much lower cost to the government. And second, private schools are likely to provide a somewhat more enjoyable education experience than one-size-fits-all public schools. I hated school and probably would have hated it less if I'd gone to a school full of students with similar interests. I'd guess other students probably feel the same way, regardless of whether they are jocks or nerds.
Megan McArdle had much higher hopes for school choice than I did, but now sees that vouchers won't perform miracles:
Between private efforts like Children's Hope Scholarships, and public voucher programs, we were finally going to get some choice into the educational marketplace. Like many of my fellow libertarians, I genuinely believed that this would be an economic and social revolution that would, over time, lift millions out of poverty and alleviate all manner of social ills.
Twenty years on, my optimism seems to have been far too exuberant. Some studies suggest that voucher programs do modest good; others suggest that they do very little; and a few suggest that the impacts are actually negative. My overall takeaway from the literature is that voucher programs probably do a little bit of good. But the emphasis is on the word "little"; they are not a cure-all, or even much of a cure for anything. It was reasonable to think, in 1997, that voucher programs could change the world. Now we have two decades of evidence.
I never thought it was very likely that school choice could lift millions out of poverty, as most poverty in America is not caused by poor quality schools.
The hope of school choice was that the worst-off kids could be given the same opportunities as those born with silver spoons in their mouths. But if what parents are most interested in is keeping their children away from those kids (at least in large numbers), that hope cannot be fulfilled. Improving the quality of instruction can make everyone better off; peer group, on the other hand, is a zero-sum game, where every child who improves their peer group must be counterbalanced by one who is pushed out.
Here I'm actually more optimistic than McArdle. I don't think rich people want their kids to attend school with other rich kids; I believe that parents want their kids to attend school with people of similar interests. Some kids are more interested in astronomy and others are more interested in high school football. Some parents want a "boot camp" school to discipline their out of control kids. This partly overlaps with class, but not entirely. We should have schools that cater to all types, so that the experience of education can be more enjoyable, or at least (in my case) less miserable. It's not a zero sum game.
We don't evaluate the quality of a Tesla by how fast it goes from zero to 60, we use the market test---do consumers want this car? Education is no different; the way to judge school quality is not test scores, it's consumer demand.
PS. One argument against school choice is that parents are not able to evaluate the quality of schools. I've never understood this argument, but I have an open mind. So here's the test I propose. Do a survey of 1000 Americans, from all walks of life. Give them a list of 30 colleges, including a bunch of Ivy League schools, a bunch of big Midwestern state universities, and a bunch of community colleges. Ask these average people to rank the schools in terms of academic quality. I'd guess that most rankings would be highly correlated with alternative rankings such as average SAT scores or the US News and World Report ranking.
PPS. McArdle's article is entitled "We Libertarians Were Wrong About School Choice". Kudos to McArdle for showing more class than most pundits, and admitting to changing her mind when new information came in. But I think that title is a bit misleading, as my argument for school choice is actually the more libertarian one (albeit not necessarily the better argument).
PPPS. I was going to do a post about how populism is not about economics, but Tyler Cowen beat me to it (and did a better job than I would have done.)