Objective: The purpose of this study was to determine classroom teachers' self-efficacy towards, and perceptions of, physical activity in the classroom. Design: The study is a convergent mixed-methods design in which both qualitative and quantitative data were collected simultaneously at one time point. Setting: A convenience sample was recruited through email from two school districts to participate in an online survey and follow-up phone interview. Method: The survey consisted of demographic variables, as well as the validated 18-item Teacher Efficacy Toward Providing Physical Activity in the Classroom Scale (TETPPACS). Quantitatively, descriptive statistics were calculated to explore general relationships; qualitatively, constant comparison and inductive analysis were used to better understand teacher efficacy and perceptions towards providing physical activity in the classroom. Results: Sixteen participants (87% female; M[subscript age] = 38.4 years, M[subscript experience] =12.25 years) representing two states and 12 schools completed both measures. Participants represented all grade levels and varied in levels of general efficacy (M = 3.18, range = 1.78-4.06), student barrier efficacy (M = 3.30, range = 1.29-4.29), institutional efficacy (M = 2.92, range = 1.33-4.22) and educational efficacy (M = 3.60, range = 2.00-5.00). Three themes emerged as part of the qualitative analysis: (1) implementation barriers, (2) the face of teacher preparation and (3) knowledge and intentionality. Conclusion: Results offer further evidence of the disconnect that exists for classroom teachers as well as insights into classroom teachers' perceptions of and self-efficacy towards physical activity in the classroom.