Sexuality is an inextricable part of every person's life, and all people get some form of education about sex in their lives, regardless of what they were taught in school. As such, it can be argued that sex education is, in fact, the most important kind of education we can provide for young people and should be a necessary requirement for all public school education. Sexuality is also inherently tied to all social identities and can impact the intersections of those identities in extremely public and political ways. The perpetuation of systemic injustice toward minoritized groups of people in the United States is mirrored in the historical and present condition of school-based sex education. For these reasons, the author argues that school-based sex education (SBSE) and all of its components (including policy, curriculum, and teacher preparation) needs a rebranding and a perspective shift in order to provide students with useful, effective, and necessary skills for creating and maintaining healthy relationships of all kinds. This dissertation study examines the history and present status of school-based sex education in U.S. public schools and calls for changes to policy, curriculum, and teacher training programs to improve the quality of SBSE across the country. [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.]