This study investigated the effectiveness of an instructional program designed to teach expository text comprehension during guided reading. Participants included 72 second graders in six classrooms, organized into four guided reading groups in each class (n = 24). The six classes were randomly assigned to one of three groups: Text Structure, Content, and No Instruction. The Text Structure group focused on text structure awareness. The Content group focused on background knowledge and vocabulary. The No Instruction group carried out their regular instruction. Findings suggest that text structure is an effective strategy for promoting expository text comprehension and that young children benefit from well-structured texts.