While recent research demonstrates that teacher noticing is a core construct of teaching, it also raises new questions about this construct. Here, we offer an expanded framework that addresses three key questions. Specifically, we suggest that attending involves not only selecting particular features of instruction to observe, but also disregarding aspects of classroom interactions that are less consequential. In addition, we propose that a stance of inquiry about observed phenomena is central to drawing inferences about observed phenomena. Finally, we extend the boundaries of teacher noticing to include "shaping," the act of creating interactions that provide increased opportunities to attend to and interpret noteworthy mathematical interactions. In other words, teachers are not simply passive bystanders in the act of noticing, rather they "shape" interactions to gain access to additional information to allow for further observation and interpretation of student thinking.