Boonsen, S. 2023. The Development of Mathematical Learning Achievement on Multiplication Using Skill Exercises for Prathomsuksa 2 Students at Suraohayeemina School. Interdisciplinary Academic and Research Journal . 3, 4 (Aug. 2023), ึ707–720. DOI:https://doi.org/10.14456/iarj.2023.215.