Improving computer science (CS) education in PK-12 continues to be a priority for educators, researchers, and policymakers worldwide. One of the leading problems and mitigating factors of student CS success, however, is the lack of teachers prepared and qualified to teach computer science. Efforts have been made to address this issue through inclusion of state and national standards, improvements in preservice teacher education programs, and funding to incentivize teachers to explore CS. Such efforts have resulted in the relatively large and instantaneous growth of teachers comparatively new to CS from a content and pedagogy perspective. The purpose of this study was to examine a large cohort of inservice teachers as they prepared to begin a CS endorsement program. More specifically, the research set out to examine their attitudes, beliefs, and self-efficacy towards CS, as well as the impact of demographics on those outcomes. Results provide evidence of the importance of continued professional development for all teachers, but specifically continued CS content and pedagogy instruction for CS integration within content areas. Additional findings point to the sustained call for diversity in CS instruction and related professional development.