This study examined the quality of classroom talk and its relation to academic rigor in reading-comprehension lessons. Additionally, the study aimed to characterize effective questions to support rigorous reading comprehension lessons. The data for this study included 21 reading-comprehension lessons in several elementary and middle schools from three urban school districts. Quantitative analyses showed that students' demonstration of knowledge and thinking talk moves during the discussion had strong, positive relationships with the level of the rigor in the lesson. Qualitatively, the lesson transcripts were closely examined to find characteristics of teachers' questions that engage students in high-level thinking. This study also discussed implications for effective questioning in classroom.