Several detours prompted me to find time in an overcrowded school day to incorporate important, powerful, daily, whole-class application of fact strategies. A few years ago, I embarked on a journey with my second graders, a journey through the strategies for mental computation of addition and subtraction facts. The focus of that journey was to help my students use their "license to think" in math, to help them happily, successfully, and fearlessly compute in their heads with understanding and fluency. I wanted my students to deepen their number sense and to realize that, for example, 8 + 9 is not something to fear. I wanted my students to see 8 + 9 and think, "I don't like you, 8 + 9, but I do like 8 + 8; and I know that is 16, and one more makes 17!"