School-based programs have been the central strategy to educate children about the serious nature of child sexual abuse (CSA) in the hope of prevention or early intervention. While program evaluations consistently show significant improvement in children's knowledge and skills, it behooves programs to monitor their impacts. Monitoring, or on-going assessments, can take several forms but in the current study refers to monitoring the outcome of knowledge of CSA prevention concepts. The "Who Do You Tell?"™ child sexual abuse education program has been offered for 35 years in Calgary, Canada and was previously evaluated in a randomized pre-test-post-test comparison study with strong positive findings. This article presents the results of subsequently monitoring program outcomes over an eight-year period (2010-2017), examining knowledge/attitudes in 6198 students in 50 schools in a Western Canadian city. All students significantly increased their CSA knowledge/attitudes with large effect sizes. Practice and policy implications are discussed.