For school this term, mum did some searching for a good writing curriculum. She came across one called One Year Adventure Novel and I'm loving it.
It's very good for creating a good story structure and helping you give your story a meaning and a goal, it also helps you to develop good characters for your story.
It's down side is it doesn't really help you in descriptive words and sentences, I would suggest a lot of quality reading if you want help in that area.
It comes with two work books and eight DVD's, with enough lessons for two lessons a week for a year.