This study explores elementary teachers' social understandings and employment of directives and politeness while facilitating inquiry science lessons prior and subsequent to their participation in a summer institute in which they were introduced to the scholarly literature on regulative discourse (directives used by teachers to regulate student behavior). A grounded theory analysis of the institute professional development activities revealed that teachers developed an increased awareness of the authoritative functions served by impolite or direct directives (i.e., pragmatic awareness). Furthermore, a comparative microethnographic analysis of participants' inquiry-based classroom practices revealed that after the institute teachers demonstrated an increased ability to share authority with students by strategically making directive choices that were more polite, indirect, inclusive, involvement-focused and creative. Such ability led to a reduced emphasis on teacher regulation of student compliance with classroom behavioral norms and an increased focus on the discursive organization of the inquiry-based science learning/teaching process. Despite teachers' increased pragmatic awareness, teacher-student linguistic relationships did not become entirely symmetrical subsequent to their participation in the summer institute (i.e., teacher authority was not completely relinquished or lost). Based on such findings, it is argued that teachers need to develop higher levels of pragmatic awareness to become effectively prepared to engage in language-mediated teacher-student interaction in the context of inquiry-based science classroom discourse.