While the core objective of centralized assignment is to expand student choice, Campos, Brhun, Chyn, and Vazquez show that, nationally, this mechanism often operates as an opt-in system, with complex options and participation concentrated among more advantaged students. Studying Los Angeles Unified School District, they confirm this pattern: opt-in choice disproportionately attracts academically and socioeconomically advantaged families. After estimating the returns to attending a choice school, they find that opt-in participation creates a selection mechanism that excludes many high-return students, who show the lowest demand for choice schools, leaving effective programs with unused capacity. Counterfactual simulations suggest that reducing information and travel costs offers limited scope for improving districtwide academic effectiveness under the existing opt-in design. By contrast, shifting from opt-in to mandatory participation reallocates students across schools, reaches students with larger causal gains, and produces the greatest increase in district-level achievement. Their results highlight the need to evaluate system design as a whole, rather than treating school effectiveness as merely the sum of individual schools, when assessing who benefits from school choice and whether the system can become more efficient.
- Working Paper: https://www.nber.org/papers/w3...