This mixed-methods study with a narrative component explored the effect athletic participation played on the academic achievement of senior student-athletes and non-athlete in a public school in Northern New Jersey. The motivation for the study was the conflicting perceptions and research as related to the impact athletic participation had on academic success at the high school levels. Through student athlete and non-athlete comparisons of G.P.A.'s, H.S.P.A. and S.A.T. scores, the researcher found athletic participation did affect academic achievement for high school seniors between the years of 2007 and 2013, as hypothesized. When comparing the six dependent variables among athletes and non-athletes, the athletes proved significant on all variables measured by using a MANOVA. More specifically, statistical significance was found in female athletes' G.P.A.s and on the S.A.T. writing section. Analysis was also obtained from the target high schools' teachers, as well as from N.J.S.I.A.A. Hall of Fame coaches. The Likert scale survey items and open-ended responses from the survey responses exposed the following regarding the academic achievement of senior student-athletes: the effect of athletic participation was mostly positive on academic performance, despite the general perception that student-athletes are sometimes treated more leniently with respect to disciplinary infractions and academic requirements; coach involvement directly affects academic achievement; athletic participation and academic achievement was important in the target school community and coaches measured success both in terms of wins and loses, as well as student-athlete character and academic performance. [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/en-US/products/dissertations/individuals.shtml.]