The fourth edition of the National Education Policy Center’s annual report on online and blended learning schools provides a detailed overview and inventory of full-time virtual schools and blended learning schools, also called hybrid schools. Little rigorous research has examined their inner workings, but evidence indicates that students differ from those in traditional public schools, and that school outcomes are consistently below traditional public schools. Nevertheless, enrollment growth has continued, assisted by vigorous advertising campaigns, corporate lobbying, and favorable legislation. This report includes student demographics, state-specific school performance ratings, and a comparison of virtual school outcomes with state norms, and provides suggestions for policymakers going forward.