I introduce the idea of the story board by finding out how many students know how their favorite animators organize their ideas. Most animated DVDs have extra material on how the movie was made. Just casually reviewing the choices on YouTube, I saw many writers who share their thought process.
I model my own story board and then talk about how to elaborate each scene using dialogue, description, and action. Some students had to elaborate in several steps, because the idea of their story wasn't clearly communicated to others.
If you have students that need a little more direction, I have labelled the four sections: Beginning, Problem, Complication, and Resolution. We talk about the elements of story and the importance of each.
You can purchase all ten forms I use for creative writing assignments and bulletin boards here in my Teachers Pay Teachers store and here in my Teachers Notebook store. I have included at least two suggestions for each form that are not here on my blog.