Kopalang, J., Prapasanobol, V. and Yuenyong, Y. 2025. The Development of Scientific Problem Solving Ability and Teamwork Skills by using Problem Based Learning and Group Investigation Technique for Grade 3 Students. Education journal Faculty of Education, Nakhon Sawan Rajabhat University . 8, 4 (Dec. 2025), 208–220. DOI:https://doi.org/10.2774.EDU2025.4.282899.