The English Language and Literacy Acquisition--Validation (ELLA-V) study was a five-year evaluation of a program that provided professional development, coaching, and curricula that targeted English-as-a-second-language (ESL) instruction for teachers of K-3 English learners (ELs). ELLA-V was implemented in 10 school districts in Texas in the 2013-14 through 2016-17 school years. The project was federally funded by a grant from the U.S. Department of Education's Investing in Innovation (i3) Fund (PR/Award Number U411B120047). Professors at Texas A&M University were the recipients of the grant and developed the professional development, the coaching program, and the curricula. Researchers at the Center for Research and Reform in Education (CRRE) at Johns Hopkins University were contracted to conduct the independent evaluation. The evaluation of ELLA-V was a multi-site cluster randomized trial designed to meet the What Works Clearinghouse (WWC) standards for rigorous education research (WWC, 2017). The study used a mixed method design to estimate program impacts on student and teacher outcomes and document the fidelity of implementation and perceived quality of the program. [This report was published at the Center for Research and Reform in Education (ED594703). Principal Investigators were Rafael Lara-Alecio, Beverly Irby, and Fuhui Tong. Cindy Guerrero and Laura Cajiao-Wingenbach were Lead Coordinators.]