We examined whether African American students differentially responded to dimensions of the observed classroom-learning environment compared with non-African American students. Further, we examined whether these dimensions of the classroom mediated treatment effects of a preschool mathematics intervention targeted at students from low-income…

"Un Buen Comienzo" [A Good Start] was a professional development program implemented with prekindergarten and kindergarten teachers in Chilean public schools serving low-income families. In a randomized trial, the program showed moderate to large impacts on classroom quality but no impacts on targeted child outcomes. To unpack these…