School psychologists have the potential to improve students' reading skills by helping schools select evidence-based programs and then supporting their implementation. Blended learning offers a flexible implementation format to address long-standing challenges implementing and scaling reading programs in schools. The purpose of this study was to explore the unique implementation challenges associated with blended learning programs, how systems-level consultation can be used to support implementation and foster intervention fidelity, and the extent to which intervention fidelity of a blended learning reading program was associated with student reading skills. This collective case study included qualitative and quantitative data from 20 schools, 666 educators, and 6208 students in the U.S. We employed mixed methods, which included inductive thematic analysis of 47 implementation plans and means difference testing to examine differences in educator engagement, student-level intervention fidelity, and student outcomes across districts with varying levels of implementation supports. Results identified several challenges encountered throughout implementation and the types of strategies employed to address those challenges. Further, results suggested that there were greater levels of fidelity and more positive student outcomes in schools accessing systems-level consultation to support implementation.