APPLICATION OF THE PJBL-STEM LEARNING MODEL ON SMOKELESS WASTE COMBUSTION DEVICE ON TEMPERATURE, HEAT, AND EXPANSION TO IMPROVE THE COGNITIVE LEARNING OUTCOMES OF STUDENTS OF CLASS VII SMPN 1 TAPUNG HULU. SPEKTRA: Jurnal Kajian Pendidikan Sains, [S. l.], v. 11, n. 1, p. 186–199, 2025. DOI: 10.32699/spektra.v11i1.8900. Disponível em: https://ojs.unsiq.ac.id/index.php/spektra/article/view/8900. Acesso em: 27 nov. 2025.