ABSTRACT
Much of the debate over the eff ects of school choice on student achievement masks an underlying and important question: How large should an education voucher be? Th e answer to this question depends, of course, on what one presumes about the eff ect of vouchers on the way students and families choose. It also depends both on other public schools’ responses to competitive pressures, and on the supply side of the schooling market. Th is chapter aims to provide a framework for thinking about the eff ect of voucher size on student outcomes under diff erent theories for how a choice system would aff ect K-12 students. Not unexpectedly, there are tensions between these theories. More surprising is the conclusion that, despite the considerable experimentation with vouchers, no program likely exists that fundamentally tests the notion that market-based competition arising from a voucher system would lead to systemic improvements in educational quality.
