This case study described teachers with varying technology skills who were implementing the use of geospatial technology (GST) within project-based instruction (PBI) at varying grade levels and contexts 1 to 2 years following professional development. The sample consisted of 10 fifth- to ninth-grade teachers. Data sources included artifacts, observations, interviews, and a GST performance assessment and were analyzed using a constant comparative approach. Teachers’ teaching actions, beliefs, context, and technology skills were categorized. Results indicated that all of the teachers had high beliefs, but their context and level of technology skills strongly influenced their teaching actions. Two types of teachers persisting in practices from professional development were identified: innovators and adapters. Persistence of practice and implementation of the integration of GST within PBI must continue after professional development ends, or the sustainability of the positive results experienced during the professional development will not persist.