The nuanced and complex cognitive and social-emotional needs of high school gifted learners are not sufficiently met through accelerated coursework like Advanced Placement and International Baccalaureate alone. Addressing their needs requires the design, implementation, and leadership of programming that maximizes their agency, curiosity, and confidence. Such programming should be fully modern in its conception and allow gifted high school students to construct and share products of their learning with respect to issues of global importance. The purpose of this study was to explore high school learning environments designed to maximize the agency, confidence, and curiosity of gifted and talented secondary students. Framed in the tenets of Self-Determination Theory, this study investigated how three secondary schools nurtured student agency, curiosity, and confidence. The study included twelve participants, four participants from each site: an administrator, a counselor, and two teachers. Rich and descriptive data was collected from two interviews of each participant, classroom and learning environment observations, and curriculum documents specific to each site. Analysis of the data identified five themes common to all three school sites: Connected Technology, Structured Questioning, Interdisciplinarity, Appreciation of Intensities, and Gradual Release. Each theme was described through the lenses of student agency, curiosity, and confidence to provide context and details pertaining to how modern learning environments can be built as courses, programs, and school to maximize the potential of gifted secondary students. [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.]