The purpose of this study is to describe how school-based sexuality education (SBSE) in the context of health education frames and teaches sexuality, sexual orientation, and gender identity. Understanding how schools address sexuality and gender provides insight into how school systems might ostracize sexual and gender diverse (SGD) youth. This study used content analysis to survey 13 health education textbooks in the United States. The content of textbooks provides a sampling of cultural, economic, and political activities and the ways they may be portrayed in the school setting. All textbooks had to be (1) health education textbooks, (2) intended for middle and high school, (3) published in the last 15 years, and (4) required or recommended by a state or local Department of Education, or produced by a publisher recommended by a department of education. Results of this study indicate that 11 of the 13 reviewed textbooks had abstinence based or abstinence only until marriage sexuality education that presented narrow, binary definitions of gender and sexual orientation, and that ignored or provided misinformation about gender identity and sexual orientation. Results of this study suggest that school personnel should consider alternatives to widely available health textbooks to teach more inclusive, affirming, and effective sexuality education.