Implementation of the curriculum-centered, standards-based federally mandated reform, No Child Left Behind, has placed pressure on teachers, particularly those working in schools comprised of highly diverse and impoverished students, to have their students attain predetermined levels on high stakes, standardized tests. When schools have not met growth targets for all subgroups of students for two consecutive years, they have been placed in Program Improvement. Schools in Program Improvement have been subject to strict monitoring by state officials and have been forced to adhere to strict schedules and time frames in which subjects are taught. They have also had to comply with limited choices in curriculum, mandated interventions, and constant assessments to monitor student progress. In many of these schools the curriculum has been narrowed to the extent that time spent on subjects such as social studies and science has been minimized, and electives such as fine and performing arts have been eliminated. Instead, the time has been spent drilling math and language arts in an attempt to ready students to pass the high stakes, standardized tests on which schools have been judged "passing" or "failing." In order to capture the experiences of teachers working in Program Improvement schools, a qualitative, phenomenological study was conducted. Eleven female teachers representing two elementary, two middle, and two high schools located in urban areas within a large Southern California county participated in audio taped, semi-structured interviews. Results of the study revealed that teachers' experiences fell into four categories: Perceived responsibilities of teachers in Program Improvement schools; perceptions of teachers regarding the curriculum-centered and assessment-driven reform; perceptions of teachers regarding the implementation and effectiveness of interventions; and change strategies teachers experienced. The responses of the teachers were in many cases consistent with the concerns expressed in the literature by critical theorists such as Freire, Giroux, McLaren, and Shor. This study challenges policymakers to reexamine the existing mandates in light of the teachers' experiences in Program Improvement schools. The implications of this study are to allow teachers freedom to make effective instructional decisions geared to the individual needs of their students and to broaden the curriculum. [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.]