I started an online course with Kris Pearn at Schoolism. The first tutorial was a introduction into storyboarding. Really good. Anyone who is serious about learning storyboarding should definitely sign up for this course. Kris is informative and very enthusiastic. Not only can you watch the tutorials, but there are also all the other students' assignments he has assessed. So far I've got a lot out of it.
Here's my first assignment. The brief was 'How did I get here?' Let me know what you think.