Using Shulman's theory of teacher knowledge as the theoretical framework and a phenomenological research design, this qualitative study used Seidman's three-interview protocol to understand how 11 kindergarten teachers perceived the CCSS affected their use of developmentally appropriate practices (DAP) and their instructional discretion. This study also examined how these teachers perceived their public school setting (rural, suburban, urban or urban charter) affected their implementation of the CCSS. Colaizzi's seven-step phenomenological methodology was employed to analyze the data into emergent themes. Five themes related to the research questions emerged from the analysis. First, the kindergarten teachers in this study perceived the CCSS to be challenging for their students. Second, the teachers identified DAP as important to their practice. Third, the teachers perceived there to be barriers to their use of DAP. Fourth, the teachers identified discretion as important to their practice. Fifth, the teachers perceived their school setting directly affected how they implemented the CCSS. Additional findings show the majority of participants perceived the CCSS negatively affected their use of DAP and that attention must be given to planning to ensure DAP's use. Finally, findings show that to maintain their discretion and use of instructional practices like DAP, the teachers engaged in fight, flight, barter, or collaboration behaviors with their principals. Findings from this study illustrate the need for teachers to play a central role in the re-examination of the kindergarten CCSS for developmental appropriateness as well as the implementation of the CCSS at the school level. Findings also show the need for school leaders to become well versed in the use of DAP to address standards and to work toward creating collaborative learning communities within their schools. Last, these findings show that the CCSS as a reform effort for improving student outcomes for ELL students and students of poverty are falling short of their intended goal. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]