Loading the library…
Showing 4 verified claims · instruction, resources & composition
High-dosage tutoring — frequent (typically >=3 sessions/week), sustained, small-group or one-to-one instruction delivered during the school day by trained tutors — is among the most reliably effective interventions for raising student achievement, with consistent positive effects across dozens of randomized field experiments; effects are largest in early grades and for lower-achieving and lower-income students.
Delaying secondary-school start times (toward 8:30 a.m. or later) reliably increases adolescents' sleep duration and is associated with better mood, attendance, and some academic and behavioral outcomes; the sleep effect is well established and replicated, while the magnitude of downstream academic gains and the practical trade-offs (transport, scheduling) are more uncertain.
The effects of grade retention are genuinely contested: rigorous regression-discontinuity studies of test-based retention find short-term achievement gains that typically fade, with conflicting evidence on later attainment — some find no effect on graduation, others find increased dropout and reduced attainment — while older observational research consistently links retention to higher dropout.