The teacher’s edition for a fourth-grade anthology suggests teaching the following words before inviting students to read an excerpt from Charlotte’s Web (White, 1952): comfort, cunning, endure, friendless, frolic, lonely, soaked, and stealthily. Why do you think these words were selected? One obvious reason for selecting words to teach is that students do not know the words. Although cunning, endure, frolic, and stealthily are probably unfamiliar to most fourth graders, comfort, friendless, lonely, and soaked are probably not. Familiarity does not seem to be the principle used to make the selection. What about importance or usefulness? Are the selected words useful for writing or talking? Would the words be important to know because they appear in other texts with a high degree of frequency? Some-but not all-of the words might be considered useful or important. Thus, the question remains: why were the words selected? The purpose of this chapter is to consider what principles might be used for selecting words to teach.