This article presents the results of a study examining a 6-month project funded by the U.S. Department of Education that focused on enhancing teacher learning and instructional practices in transitional kindergarten (TK) in a large urban California school district. The project integrated and adapted the Doing What Works (2012) dialogic reading practices into ongoing professional development for 28 TK teachers working in classrooms with high percentages of 4- and 5-year-old dual language learners (DLLs). We employed a quasi-experimental design that used a comparison group to examine how teaching practices changed both with and without the project's coaching support. Data from classroom observations, teacher surveys, and coaching reflections indicate that implementation of scaffolded dialogic reading practices improved TK teachers' knowledge and oral language instructional strategies for teaching DLLs. (author abstract)