Later school starts boost equity

A California statewide mandate (SB 328) that moved middle and high school start times later increased the share of students sleeping at least eight hours by 13% and produced modest gains in 8th‑grade math and English (≈0.08–0.10 SD), with the largest benefits for Hispanic and economically disadvantaged students and some reductions in boys’ suicidal ideation. The paper uses difference‑in‑differences and event‑study designs plus multiple data sources and a teacher‑commute proxy to triangulate effects over 2023–2025. — If later start times reliably improve sleep, cognition and mental health — especially for disadvantaged groups — statewide scheduling is a low‑tech policy lever that intersects education, public health, and equity debates.