Reading and Language Outcomes of a Multiyear Randomized Evaluation of Transitional Bilingual Education

Multiyear RCT, Spanish-dominant US children: transitional bilingual education group significantly worse in English reading and vocabulary in grade 1, gap shrinking in grades 2–3 and gone by grade 4. Holds at the end, but an early reliable English deficit bounds "do not lower reading by any reliable amount". 2010 report full text: −0.54 (K), −0.42 (grade 1), then −0.20/−0.16/−0.25 (grades 2–4, 1 of 9 significant). C34 weakened 2026-11-01.