Although many states mandate college preparatory curricula for all high school students, there is no conclusive evidence regarding the benefits of this effort. Furthermore, we know little about how schools interpret and implement such policies. This extended ethnographic case study included a 4 year examination of 1 Michigan high school's response to a state policy mandating college preparatory curricula for all high school students. Using interviews with 10 administrators and 22 teachers, observations of 13 mathematics and 12 science classes, and various related documents, we examined how these school-based educators made sense of and implemented this policy. Data analysis was guided by Anthony Giddens' (1984) structuration theory about the recursive relationship between structure and agency. Our findings reveal how administrators and teachers, in responding to the policy, created structures that unintentionally hurt the struggling students they were trying to help. We recommend additional resources to assist those responsible for implementing policy in public schools.