The impact of teacher observations in alignment with professional development (PD) on teacher efficacy was quantified for 292 schools in 110 districts within 27 U.S. States. Teacher observations conducted by school leaders or designated internal coaches were coordinated with PD offerings aligned with intended teacher improvements. The PD involved throughout was an online, on-demand system teachers accessed as convenient with a range of PD assistance regarding teaching techniques and participative teacher/user interactive communities for collaboratively posting and downloading PD-related materials. Results indicate that systemic teacher observations, coupled with aligned PD, resulted in significantly improved student achievement in reading and math on standardized assessments.