In 2019, declines in reading achievement across Texas motivated changes for teacher recertification, which required 60-hour professional development in the science of teaching reading (STR). The problem this study addressed was the challenges K-Grade 3 reading teachers encountered when implementing the recently adopted Reading Academy content at a large urban school in Texas. The purpose of this basic qualitative project study was to explore the challenges K through Grade 3 reading teachers encountered when implementing the recently adopted Reading Academy content at a large urban school in Texas. The implementation science conceptual framework guided this study on the fidelity of implementation regarding the House Bill 3 reading practices. This study's research question focused on teachers' perceptions regarding the challenges of implementing the STR practices. Data were collected from semistructured interviews with 10 kindergarten through third-grade teachers. The educators had completed the Reading Academy and implemented the STR strategies in their classrooms. In vivo, coding was used to analyze the data. Three themes emerged: student reading levels, sufficient time for reading instruction and learning STR strategies, and access to STR materials. The project involved professional development training divided into eight modules for teachers to build their capacity in reading instruction. Findings may be used to improve administrative support for teachers to implement STR strategies, which may result in more gains in student reading achievement. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]