Trongsakul P, Thammaprateep J, Phadungphatthanakoon S. The Development of Science Competency through Problem-based Learning in the Topic of Changes in Matters of Grade 5 Students at Ban Thung Chon School in Nakhon Si Thammarat Province. edjour_stou [internet]. 2026 Jun. 29 [cited 2026 Sep. 11];19(1):55-83. available from: https://so05.tci-thaijo.org/index.php/edjour_stou/article/view/286331