According to NSF (2017), even though the number of minority students in America's college-age population has been on the rise, those who choose Science, technology, engineering, and mathematics (STEM) as their majors are significantly fewer. There is an urgent need for African Americans, being the underrepresented minorities in STEM-related domains, be provided with opportunities to increase their presence and achievements (Hansen, Palakal & White, "Journal for STEM Education Research," 1-26 2023). This paper was to develop an active flipped learning (AFL) model to enhance engineering students learning. Instructional video, audio, lecture notes, and reading materials are developed while initiating active learning activities in class to engage students in active flipped learning. By monitoring 103 students' engagement and identifying their motivation and learning strategies, a custom-tailored plan to fit each underrepresented student in STEM was formed, valued by two indicators: Engaged Learning Index and Motivated Strategies for Learning Questionnaire. After practicing the longitudinal research for three years from 2016 to 2018, some results were found during the procedure through ANOVA and correlation analysis on the collected data. The AFL model effectively promotes underrepresented students' performance in various science disciplines such as engineering, physics, and mathematics, such as helpful to foster underrepresented students' deep understanding of STEM disciplines and making them more engaged in STEM learning. In the future, the AFL can be potentially expanded to other institutions to help all students succeed in STEM classrooms and careers, to increase the national STEM literacy and be applied to non-STEM majors.