Teacher organization is a crucial part of classroom functioning; however, its relation to student achievement has not been investigated as extensively as that of instruction. In this study, organization is defined as the amount of time teachers spend explaining the purpose and procedures of learning activities and daily routines. Data from first-grade classrooms (N = 44) observed three times during the school year (fall, winter, and spring) are analyzed, along with students' (N = 108) literacy skills at fall and spring. Hierarchical Linear Modeling reveals that, controlling for students' fall word reading and vocabulary skills, as well as amount of language arts instruction they receive, both amount and change in amount over time in classroom organization significantly predicts spring word reading skills. Specifically, children in classrooms observed in higher amounts of classroom time in organization at the beginning of the school year, followed by sharp decreases over the school year, demonstrated stronger letter and word reading skills by spring, and this was a main effect (p less than 0.05). Practical and research implications are discussed.