ชมภู บ. Comparisons of Learning Achievements, Analytical Thinking Abilities, Satisfaction with Learning and Teaching, and Learning Retention in the Mathematics Learning Strand Entitled Trigonometrical Ratios of Matthayomsueksa 4 Students Using Courseware Geometer’s Sketchpad Approach (CGS) and the Conventional Teaching Approach. J.TNSU [internet]. 2010 May 3 [cited 2026 Sep. 18];2(1):155-6. available from: https://he02.tci-thaijo.org/index.php/TNSUJournal/article/view/252168