Mixed-major biology courses are often utilized by kinesiology programs to provide essential foundational material to prepare students for higher-level courses within kinesiology. There has been an increase in overall kinesiology students in these mixed-major biology courses. Despite this significant shift in student demographics, faculty in mixed-major biology courses have not adjusted their instruction, missing vital opportunities to engage students from academic majors outside of the biological sciences with course content that prepares them for their academic majors. Faculty must utilize instructional models that allow students to succeed across various academic disciplines, especially students from kinesiology-related majors. The purpose of this study was to understand the current approaches of biology faculty in their mixed-major courses through classroom observations and course artifacts. Semi-structured interviews were used to identify faculty needs and attitudes toward an adapted differentiated instructional (DI) approach based on career pathway. Analysis provided insight into current faculty practices and their perceptions of teaching students from kinesiology-related majors. Eight themes emerged across the two specific aims of this study. Results indicated a disconnect between actual teaching practice and perceived practice as well as a lack of understanding of the diverse majors that make-up their mixed-major biology courses, specifically kinesiology majors. Recommendations for action items included the need for interdepartmental collaboration between biology and kinesiology faculty and led to the creation of the Interdisciplinary Taskforce for STEM Success (ITSS) to provide a relationship between the science and kinesiology programs. Further development and expansion of this taskforce will address faculty needs as it relates to the incorporation of DI based on career-pathway in mixed-major biology courses. [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.]