The Texas Earth and Space Science (TXESS) Revolution was a 5-y teacher professional development project that aimed to increase teachers' content knowledge in Earth science and preparing them to teach a 12th-grade capstone Earth and Space Science course, which is new to the Texas curriculum. The National Science Foundation-supported project was designed around six principles that proved to be critical to in its success: (1) model best practices in workshop presentations, (2) use authentic Earth science data and cybertechnology to teach up-to-date content, (3) provide ongoing training to cohorts of learners over a 2-y period, (4) involve geoscience consortia and programs that can provide proven content for classrooms, (5) use ongoing evaluations to guide future workshops, and (6) provide opportunities for leadership development through participation in research and curriculum development projects. The project served 177 science teachers by supporting them with the pedagogical, technological, and scientific tools to teach modern geoscience. TXESS Revolution teachers directly impacted more than 29,000 students, of which about 69% are nonwhite, by exposing students in Texas to the geosciences and planting the seeds for them to pursue geoscience as a field of study. Using a train-the-trainer approach, TXESS Revolution teachers shared their professional development with other Texas teachers, strengthening Earth science education at all K-12 levels throughout the state, an impact that extends beyond preparation in Earth and space science. Ó