This action research study examines the integration of K-12 online learning curriculum in a graduate instructional technology course aimed at preparing in-service teachers for online teaching environments. Through a cycle of curriculum implementation, data collection, and analysis, the study highlights the evolution of teachers' perceptions, identifying both the benefits and challenges of online education. Findings suggest that curriculum changes can significantly impact teachers' understanding and attitudes, though the study is limited by its small sample size and single-site context. Despite these limitations, the study offers valuable insights for teacher education programs seeking to incorporate online teaching components. Future research should consider expanding to multiple sites and updating curriculum content to reflect post-pandemic experiences in digital learning environments.