Rule 4: Once upon a time, there was ____. Every day, ____. One day, ____. Because of that, ____. Because of that, _____. Until finally, _____.
I wish I'd had something written out so simplistically when I assigned creative writing projects to middle schoolers. Because without this, no matter what I explained or told the little darlings, they would spring forward from a winning opening line and never look back. They never really looked forward, though, either. As pre-teens tend to do, they didn't really pay attention to anything except what was right in front of them. This made their stories about one person to whom five-hundred things happened, with no connection between events and no resolution in sight.
Rule #1 explained that our hero must fail, preferably several times, before he succeeds in the end. If he succeeds in the end. This rule simply applies a structure to that rule, and prevents what I call, "The Downfall of the Middle School Writer."
Basically, love your character. Build your character. Make them whatever you think they should be. ore But remember to put them in situations that will be difficult. Better yet, have some idea what those situations will be, and have an ending in mind as you write. A lot of writers rail against this, because writing is a magical process that comes from within, unfolding before us in a mysterious and wonderful way. But if your story is meant to be quite good, to have purpose and to please an audience, you might want to have an end point. Otherwise, you'll do what the middle schoolers do: go on and on and on and be very surprised when you just get tired of writing.
And it isn't just Pixar that came up with this as a structure. Pixar, wildly successful and stupendously awesome Pixar, was just smart enough to know that utilizing a formula--as a starting point only--makes a solid and complete story every time. You can change things as you can go. You can rewrite and revise and be true to your character and your craft, but without structure and control, you won't end up with a very good story. I know one particularly great writer who was a great fan of this. His name was Shakespeare and he called it the three-act play.
Please check out what the other bloggers are saying about Rule #4!