The current study examined the effect of a web-based literacy program, Raz-Plus, that serves as a resource for blended learning instruction in K-5 classrooms. Following a 13-week implementation period at three rural elementary schools, comparisons of the treatment (21 teachers and 249 students) and control (18 teachers and 198 students) groups revealed greater outcomes in the treatment group for overall literacy achievement, student interest in academic reading, and student interest in recreational reading, as compared to the control group. Core dimensions of implementation fidelity were measured through classroom observations and surveys with participating teachers; analyses revealed no significant associations between fidelity measures and student outcomes. This study provides evidence of the efficacy of Raz-Plus as a tool for supporting literacy development of elementary students. Additional research is warranted to determine the elements of implementation that support optimal student outcomes.