Thanks to private-school choice—vouchers, tax-credit scholarships and education savings accounts—this year nearly half a million children in 29 U.S. states and the District of Columbia will attend schools their parents selected.

Critics of school choice often argue that low-income families lack the knowledge or ability to choose meaningfully between schools. Worrying that parents will be taken advantage of or make poor decisions, they oppose choice programs or favor onerous testing requirements to prove they are effective.

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