It is a healthy exercise to debate the merits of using effect-size benchmarks to interpret research findings. However, these debates obscure a more central insight that emerges from empirical distributions of effect-size estimates in the literature: Efforts to improve education often fail to move the needle. I find that 36% of effect sizes from…

Every Classroom, Every Day (ECED) is a set of instructional improvement interventions designed to increase student achievement in math and English/language arts (ELA). ECED includes three primary components: (a) systematic classroom observations by school leaders, (b) intensive professional development and support for math teachers and…

This randomized control study compares the efficacy of two response-to-intervention (RTI) models: (1) Dynamic RTI, which immediately refers grade 1 students with the weakest skills to the most intensive intervention supports (Tier 2 or Tier 3); and (2) Typical RTI, which starts all students in Tier 1 and after 8 weeks, decides whether students who…

This study investigates, through a cluster randomized trial, the impact of "Math in Focus," a core mathematics program modeled after instructional approaches used in Singapore, on third- through fifth-grade students' achievement in mathematics. The program is currently being used in more than 400 school districts in the United States.…