to three times larger among fourth and fifth graders in North Carolina than among kindergarten and first-grade students … both low-income students and English language learners, particularly for reading achievement. Also, in North Carolina …

socio-economic and academic skill composition of schools. We exploit the quasi-random reassignment of students across …, increasing the achievement levels of students' peers improves students' math and ELA test scores but harms their ELA course … grades. Test score benefits accrue primarily to students from higher-income families, though students with lower family …