Development ISTOPAN: a manipulative learning media for improving conceptual understanding and supporting students’ learning motivation in addition with regrouping. Indonesian Journal of Primary Education, [S. l.], v. 10, n. 1, p. 119–134, 2026. Disponível em: https://ejournal-tasikmalaya.upi.edu/ijpe/article/view/295. Acesso em: 28 sep. 2026.