THE EFFECTIVENESS OF USING ORIGAMI BOARD MEDIA IN UNDERSTANDING THE CONCEPT OF PERIMETER OF FLAT SHAPES AMONG ELEMENTARY SCHOOL STUDENTS. Fundamental Journal of Elementary Education, [S. l.], v. 1, n. 2, p. 11–15, 2025. Disponível em: https://journal.cerdasnusantara.org/index.php/fundamental/article/view/83.. Acesso em: 28 oct. 2025.