The good news about the Common Core State Standards: They emphasize writing convincing arguments about issues that matter, clear and comprehensive informational texts that can do meaningful work in the world, and compelling narratives. The bad news: Traditional approaches to teaching writing aren't enough to meet these new standards. The problem: Traditional instruction does not develop all of the kinds of knowledge writers need. The authors' solution: Writing teachers should seek to develop the five kinds of knowledge that expert writers need by regularly engaging their students in five kinds of composing. (Contains 1 figure.)