The education research community is trying to figure out how to foster and assess responsive teaching, which in turn requires us to conceptualize what counts as progress toward greater responsiveness. As we discuss below in our literature review, much of the existing work on teacher noticing/attention/responsiveness describes responsive teaching in terms of levels (or a spectrum), with greater responsiveness consisting of more attention to the substance of student thinking and more responses that interpret rather than correct students’ ideas. These accounts often treat a teaching episode as “more” vs. “less” responsive or as “responsive” vs. “not responsive.”