Research in integrated learning systems has demonstrated a need for rigorous studies that identify how such systems influence learning, and in particular that of low achieving students. No Child Left Behind legislation mandated evidence-based interventions as the standard for instructional approaches in American public schools. This quasi-experimental study investigated the impact of Merit literacy software on students in West Virginia. The study confirmed that the software supported the reading and language arts curriculum and significantly improved the scores of low achieving middle school students on three variables of the WESTEST, a criterion-referenced state test: reading and language arts, science, and social science. This integrated learning system was effective with rural and urban school populations.