This study explores questioning practices adopted by elementary teachers while facilitating science inquiry discussions prior and subsequent to their participation in a summer institute in which they were provided with scholarly descriptions of inquiry-based teacher questioning (i.e., typologies of questions used by discourse analysts to categorize and understand teacher questioning) and conducted video-based discourse analysis. Teachers' questioning is examined in light of their social understandings (i.e., how teachers understand social aspects of oral questioning in inquiry-based science classrooms). The reported findings show that, as a result of developing an increased awareness of social aspects of teacher questioning during the institute, teachers' referential questions (oral queries aimed at encouraging students to articulate their own ideas, understandings, experiences and personal opinions) were twice as frequent after the institute as they were before, hence suggesting an increased degree of student-centeredness. Furthermore, their student-centered questions prompted longer and more articulated student responses, promoted higher-level student thinking, positioned students as complementary experts, prompted students to provide tentative responses, and encouraged students to conduct authentic investigations. Based on these findings, it is argued that educators who set out to prepare teachers to become effective questioners in the context of science inquiry discussions ought to go beyond cognitive issues and the simple provision of static and ill-defined labels such as "guide" and "active inquirer." (Contains 4 tables and 3 figures.)