Please spend the entire period creating your main characters and then developing the first detailed background for your CYOA. By the end of the period you should have at least two main characters and the background for your animation. If possible, please start creating movie clips as well. Your characters will move and will therefore be mostly movie clips at some point.
Remember, at the end of the each section the game player will need to decide what to do next. I will go over how to create buttons and action script that will allow you to "code" your game on Friday.