This case study involved examination of the evolution of mathematical beliefs of three prekindergarten teachers. The researcher followed three teachers at one school in west Alabama over the course of 6 months as they implemented a new mathematics curriculum in their pre-K classrooms. Interviews were conducted prior to implementation and at the end of the school year. Classroom observations were done throughout the implementation process. Three themes emerged from the data (a) math resources for the pre-K classroom, (b) pushing beyond--thinking mathematically, and (c) instructional strategies used the pre-K classroom. These themes revealed how all of the teachers' perceptions of early childhood mathematics curriculum and instruction evolved during the course of the study. These findings have implications for early childhood teacher education programs and professional development.