Jantima, Nareekarn, and Natthiya Chaichana. 2026. “The Development of Scientific Skills and Learning Achievement on Rocks and Fossils of Grade 6 Students at Phanpasoksawad School Using GPAS 5 Steps Learning Approach”. Education journal Faculty of Education, Nakhon Sawan Rajabhat University 9 (2). Nakhon Sawan,Thailand:30-45. https://doi.org/10.2774.EDU2026.2.285183.