THE FUSED health education series was developed as a one-stop guide for developing a quality curriculum for teaching health education. This first, two-part article introduces a new approach to teaching health education called THE FUSED Technique. THE stands for Teaching Health Education and FUSED stands for Functional (data driven) information, Using health-behavior outcomes (HBOs), Skill-based cues, Engaging teaching strategies, and Daily application in developing health-literate K-12 students. THE FUSED Technique was developed to teach health skills and content to today's K-12 learners. It focuses on lifelong health literacy and helps bridge standards-based and skill-based health education. At its core, FUSED is a skill-based health education teaching technique that engages K-12 students by using a variety of participatory methods to ensure that students have ample opportunities to practice and develop the knowledge, skills and attitudes needed to lead healthy lives. Part 1 of this article describes how to build a FUSED unit and lesson, and Part 2 will describe how to implement a FUSED lesson.