Jesi Agustina Panjaitan, Andrino Manalu and Selamat Triadil Saragih (2023) “The Influence of Problem Based Learning (PBL) Model on Students Science Skill in Material of Substances and Alteration Changes at Grade IV UPTD SDN Percontohan”, International Journal of Integrated Science and Technology, 1(5), pp. 645–656. doi: 10.59890/ijist.v1i5.707.