School districts have recognized the undeniable power of using data to enhance performance. As a result, teachers are now required to use data to prepare for critical state assessments and to improve district levels. These assessments are crucial in determining the school's rating by the state and can even result in a state takeover if scores are unsatisfactory. Since English/Language Arts and Mathematics are the emphasis of many schools, science teachers have not been equipped with these trainings because Science subjects are not tested as much. This study of 18 science teachers used mixed methods to gather quantitative and qualitative data, incorporating surveys and focus groups, offering a more comprehensive understanding of the breakdowns and barriers associated with data-driven decision-making. By implementing these methods and providing training, significant improvements were observed in students' assessment scores and teachers' comfort levels. The training played a crucial role in equipping teachers with the skills and knowledge needed to proficiently analyze data and identify specific focus areas for individual students. I close by addressing implications for research and practice that tell how by providing teachers with the essential tools and expertise to analyze data, they can better understand their students' strengths and weaknesses and tailor their teaching accordingly. [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.]