What is a storyboard? It's a place to plan out your digital story in two dimensions. The first dimension is time: what happens first, next, and last. The second is of interaction: how does the voiceover (your story) interact with the images, how do visual transitions and effects help tie together the images, how does the voiceover interact with the musical soundtrack? Any element can interact with any other one, and the storyboard is the place to plan out the impact you intend to make on the audience.
You must plan out your animation in the form of a storyboard! Don't wory about the quality of drawing!, it is only to demonstrate graphically the order and timing of the sequence.