Expanded learning time (ELT) is a practice that increases the length of the school day for all students, with the goal of using the additional time to improve student outcomes, especially in low-performing schools. Since 2006, Boston Public Schools (BPS) has been implementing ELT in an effort to improve student outcomes and narrow opportunity and achievement gaps.

As part of a federally funded Researcher-Practitioner Partnership, BPS is collaborating with AIR to study its ELT program types, with the goal of understanding the impact of ELT on student academic and behavioral outcomes, as well as program cost-effectiveness.

In Year 1 of the project, BPS identified 46 schools implementing ELT, and AIR and BPS staff interviewed school administrators and staff to begin to understand how schools were choosing to use expanded time, as well as the strengths and challenges of implementing ELT. In the second, and final, year of the project, data from 2005 to 2016 were used to understand the impact of ELT on student achievement for BPS students.

Key Findings

Among the findings for students in ELT schools:

• A statistically positive impact was found for all students in English language arts and mathematics in each of the first two years after ELT implementation. The improvements were larger in mathematics than in English language arts, and no impact was found for science achievement.
• The data show a positive impact in each of the first two years after implementation for several different demographic groups in both mathematics and English language arts, including Black, Hispanic, female, and male students. Some gains were observed for economically disadvantage students and English language learners, primarily in Year 2. No impact was found for White or Asian students or students with disabilities.