Musfirah et al. 2026. Implementation the Problem Based Learning (PBL) Model Assisted by Pop-Up Book Media to Increase the Activeness of Science Learning in Class V Students of UPTD SD Negeri 85 Parepare. International Journal of Sustainable Applied Sciences. 4, 7 (Jul. 2026), 585–596. DOI:https://doi.org/10.59890/ijsas.v4i7.16.