According to the United States Department of Education, approximately 1.2 million students drop out of high school every year, and of those public high school students who enter college, nearly half require remedial courses, and fewer than half ever graduate college. There have been multiple research studies conducted on the importance of student engagement as an influencing factor for student success and the importance of the successful transition from middle to high school. The purpose of this qualitative exploratory case study is to explore, compare, and contrast the themes, patterns, and reasons that might be potential determinants of a decline in student engagement in on-task behaviors and active participation in the learning environment in public schools. Interviews were conducted with 14 participants to elicit input on the perceptions and reasons related to the continuing decline in student engagement as students make the transition from middle school to high school in the public school system. A total of five themes emerged as reasons for the continuing decline in student engagement in on-task behaviors and active participation in the learning environment. The themes were (a) inconsistency in understanding the importance and impact of student engagement, (b) challenges with current instructional methods, (c) varied perceptions on key student engagement influencers, (d) conflicting perceptions on key motivational factors, and (e) schoolwide and district-wide challenges and barriers. The study highlighted participants inconsistency in understanding the importance of student engagement to student success. Participants overwhelmingly agreed and suggested that a district-wide initiative needed to be in place to change the current instructional methods, which were considered to be ineffective and contributing to the high decline in student engagement. The results of the study also supported the HSSSE survey results on the key engagement influencers and motivational factors impacting student engagement. Lastly, the study findings suggest a need for district-wide programs to tackle the various challenges and barriers by developing and implementing a comprehensive improvement program. This program should meet the legislature requirements and improve overall student engagement as students transition from middle school to high school. [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.]