This ethnographic study focused on understanding the culture and describing the experiences of elementary mathematics teachers as they used a mandated curriculum and scope and sequence at a state-supervised school. The scope and sequence was created and provided by the school district with the expectation of implementation with high fidelity by the Bureau of School Improvement within the state of Florida. This study used key informant interviews, Professional Learning Community observations, and classroom observations of mathematics teachers in grades three through five to analyze and describe how the school culture of planning and instruction influenced mathematics teaching. Findings suggest that strict expectations and frequent observations from the district and state impacted the school culture, which put pressure on teachers to follow the mandated curriculum with high fidelity. Despite the mandates and strict expectations, many teachers still perceived to have some autonomy to adapt their instruction with the goal of meeting students’ needs. Participants prioritized what they considered most important from the district resources. This led to changes related to pacing and small group instruction. The discussion of the findings connects to previous research on how mandated curriculum impacts teacher autonomy and how school culture is developed and shaped. Recommendations for future research and practice focused on increasing mathematics instructional time and creating equitable structures for students where they can build deep mathematical understanding in a flexible space of time.