Teachers Pay Teachers, an online marketplace, is a source of millions of free and paid instructional materials for educators. The site says 85% of US teachers have used it, with over 98% using it monthly. Despite the site's popularity, little is known about the quality of the instructional materials it offers. Given its widespread use, it is critical to evaluate the appropriateness and quality of health education resources to ensure the materials are accurate, standards-aligned, and free from information that could have a negative impact on students. The purpose of this study was to evaluate the quality of free health education lessons. Content analysis, a researcher-developed rubric, and frequency calculations were employed to describe the resources and assess their quality. Over three-fourths of lessons were rated as poor or fair in overall quality. Many failed to align with standards, lacked functional health knowledge, or did not reflect Universal Design for Learning principles. The findings raise concerns about the quality of instructional materials and their potential negatively impact student learning in health education and, ultimately, lifelong health behaviors. Health educators should take the lead in developing appropriate health education resources on these sites. The profession should advocate for stronger review processes and the development of clear quality indicators on online marketplaces. Future research is needed to examine the quality and use of paid resources, as well as the factors that influence educators' purchasing decisions.