The Impact of the Bilingual/Biliterate Instruction for Bilingual Youth (BBILY) Program on Student Achievement

Abstract

The Bilingual/Biliterate Instruction for Bilingual Youth (BBILY) program provides online professional learning in Spanish to strengthen teachers’ bilingual and biliterate instruction. This study examined BBILY’s impacts on students’ English language arts achievement, Spanish language arts achievement, and English language proficiency after one year of implementation. Using a quasi-experimental design and California administrative data, we compared students in grades 4–8 taught by BBILY teachers with students taught by nonparticipating teachers. Three comparison approaches—involving survey respondents, propensity score–matched teachers, and districtwide eligible teachers—were used to assess the consistency of findings. Analyses adjusted for baseline achievement and observed student, teacher, and school characteristics. No statistically significant impacts were detected on English language arts achievement or English language proficiency across the three approaches. Spanish language arts estimates were consistently positive, with a statistically significant effect of 0.29 standard deviations in the matched comparison analysis. However, the Spanish language arts findings should be interpreted cautiously given the small analytic sample. The results provide suggestive evidence of benefits for Spanish literacy, warranting replication with larger samples and longer follow-up periods to examine potential longer-term impacts on Spanish and English literacy.