Although prior research has examined critical literacy through qualitative case studies, no known study has been conducted on a cross-case mixed-methods exploration of the practices used to teach critical literacy. Furthermore, in the literature, critical literacy is typically described as a theory rather than a practice. I present the quantitative portion of a mixed-methods exploratory sequential design study, in which I sought to operationalize and validate the construct of critical literacy as teacher practice and determine the factors of critical literacy instruction. I used findings from the qualitative study to develop an instrument that collected data regarding teachers' instructional practices, and I used the instrument to quantitatively collect data and determine the factors of critical literacy pedagogy via confirmatory factor analysis. Results indicated a seven-factor structure: Relevant, Reflexive, Deconstructive, Dialogic, Empowering, Transformative, and Intersectional. Model fit was excellent, indicating that the data were predominantly captured by the seven-factor structure, thus defining critical literacy theoretically (a combination of postmodernism, poststructuralism, critical theory, culturally relevant teaching, and intersectionality) and through the pedagogical practices represented in the scale items. Understanding how the theories differ quantitatively may allow researchers to continue exploring critical theories and pedagogies quantitatively, as well as provide better theoretical understandings to other postmodern, poststructural constructs. Additionally, the resulting scale provides a quantitative tool that can be used to further current and preservice teachers' understandings and applications of critical literacy instruction.