A new reading can lose effectiveness if not implemented consistently by all teachers. The purpose of this study was to understand how first grade teachers perceived implementation of the Core Knowledge Language Arts (CKLA)reading program and what challenges they encountered when using the program. Three research questions were explored in the study. RQ 1: How do first grade teachers perceive the Core Knowledge Language Arts reading program? RQ 2: What challenges do first grade teachers experience when teaching the Core Knowledge Language Arts reading program? RQ 3: How do first grade teachers implement the reading program as evidenced by their lesson plans? First grade teachers along with special education and Title 1 teachers who support first grade students were interviewed. The teachers who participated in the study had been trained in using the CKLA reading program. The interviews were transcribed into Microsoft Word documents and participants checked the transcriptions for accuracy. Through content analysis of the interviews, three themes from the interviews emerged. They were: 1) Strong Reading Skills Core, 2) Insufficient Interventions, and 3) Inadequate Writing Instruction. Dwecks mindset theory guided this study.