Jansrahang S, Soikudrua N, Khechornphak T, Rundon B, Somtaw T. The Development Learning Activities on Concentration by using Polya’s Problem Solving Process with Multimedia for Mathayomsuksa 4 students Phadungnaree School. JDSC [internet]. 2023 Dec. 31 [cited 2026 Sep. 2];10(3):567-86. available from: https://so03.tci-thaijo.org/index.php/rdirmu/article/view/266670