For decades, educators have hoped to integrate geospatial tools into K-12 classrooms but struggled with barriers of time, technology, and curriculum alignment. The authors formed a design partnership with ninth-grade science and social studies teachers in an urban high school in order to conduct teacher professional development while also developing geospatially enabled curricula to enact in their classrooms. This article includes a description of the curriculum design principles and processes, as well as an explanation of the professional development strategies as participants worked shoulder to shoulder in designing engaging classroom instruction to enhance students' geospatial thinking and reasoning skills. One of the activities presented is an example of the design and development process, and lessons learned from the pilot test implementation are presented. This article may inform similar work with geospatial technologies in teacher professional development and curriculum development.