The best alternative depends on what you actually need: self-paced reference material, interactive practice, 3D visualization, instructor support, or formal academic credit.
Downloadable self-study
Useful when you want offline reading, printable diagrams and flexible pacing.
Interactive platform
Better suited to learners who want quizzes, visual exploration and digital feedback.
Textbook + atlas
A traditional route with stable reference material and strong visual support.
Formal course
Appropriate when you need instructor-led learning, assessment, prerequisites or academic credit.