Teachers are required to use evidence-based practices while teaching their students with autism spectrum disorder. However, there is considerable research suggesting that they need professional development (PD) to use evidence-based practices. Therefore, research needs to search for effective and efficient PD alternatives have arisen nearly during the last two decades. The researchers used an adapted alternating treatments design to compare asynchronous web-based PD with and without coaching to train three special education teachers to use social stories and video modeling procedures when teaching safety skills to three students with autism spectrum disorder. Results showed that teachers acquired the steps of these procedures with a mean of at least 95% accuracy across three consecutive sessions using both web-based PD with and without coaching, maintained these steps over time, and generalized them when teaching new behaviors to their students. Web-based PD without coaching was more efficient in two teachers, but this finding could not be replicated for the third participant. Results also showed that students learned targeted safety skills through these procedures. Finally, teachers' opinions of the social validity of the study, collected in a time-series design, showed positive changes from the beginning to the end of the study.