The effect of flash card media and problem-based learning to critical thinking skills in elementary school science lessons. Primary: Jurnal Pendidikan Guru Sekolah Dasar, [S. l.], v. 14, n. 5, p. 738–747, 2025. DOI: 10.33578/jpfkip.v14i5.p738-747. Disponível em: https://primary.ejournal.unri.ac.id/index.php/JPFKIP/article/view/171. Acesso em: 29 oct. 2025.