Ultrasound (US) imaging is a valuable tool used in many medical disciplines. Currently, there is a lack of standardized US education among Canadian medical schools, and accordingly, limited introductory resources. Challenges such as orienting US planes, translating between 2D images and 3D anatomical relationships, and interpreting structures in grayscale, present a steep learning curve for novice learners. This project aims to enhance undergraduate medical US instruction by creating, evaluating, and sharing an online interactive Sonoanatomy Atlas. The modular atlas covers fundamental US principles, 3D shoulder anatomy, and a shoulder scanning protocol. It integrates user-controlled 2D and 3D components that allow users to interactively explore how US interacts with shoulder anatomy. Instructional animations of the procedural US techniques synchronized with real scans help demonstrate the complex and dynamic anatomy, and color illustrations of each US scan facilitate development of interpretive skills. We hope to evaluate the resource with students and instructors to assess integration into curriculum, perceived efficacy, website traffic and engagement, and content understanding.