<![CDATA[Penelitian ini berawal dari dominasi metode konvensional (ceramah) yang kurang memberi kesempatan bagi siswa untuk membangun pengetahuannya secara mandiri, sehingga hasil belajar IPA masih rendah. Penelitian ini bertujuan mendeskripsikan penerapan model Problem Based Learning (PBL) berdiferensiasi berbasis konstruktivisme dalam meningkatkan hasil belajar IPA siswa kelas IV. Model yang dikembangkan mengintegrasikan pendekatan PBL yang berfokus pada pemecahan masalah kontekstual, teori konstruktivisme yang menekankan pembentukan pengetahuan aktif, serta diferensiasi pembelajaran dalam aspek konten, proses, dan produk guna mengakomodasi perbedaan gaya belajar siswa. Penelitian dilaksanakan di SD Negeri 26 Membalong dengan subjek 14 siswa (6 perempuan dan 8 laki-laki) pada tahun ajaran 2025/2026. Metode yang digunakan adalah Penelitian Tindakan Kelas yang meliputi tiga tahapan: pra-siklus, siklus I, dan siklus II. Hasil penelitian menunjukkan bahwa penerapan model ini berlangsung efektif dan sistematisNilai rata-rata hasil belajar siswa meningkat dari 58,6 pada pra-siklus menjadi 76,4 pada siklus I, dan mencapai 92,9 pada siklus II. Peningkatan tersebut menunjukkan bahwa penerapan Model Problem Based Learning (PBL) Berdiferensiasi Berbasis Konstruktivisme berpengaruh positif terhadap peningkatan hasil belajar IPA siswa kelas IV. Dengan demikian, PBL berdiferensiasi berbasis konstruktivisme terbukti mampu menciptakan pembelajaran yang adaptif, bermakna, dan berpotensi meningkatkan hasil belajar kognitif siswa. Implementation of Differentiated Problem Based Learning Model Based on Constructivism to Improve Science Learning Outcomes Abstract This research started from the dominance of conventional methods (lectures) which do not provide students with the opportunity to build their knowledge independently, so that science learning outcomes are still low. This study aims to describe the application of a differentiated Problem Based Learning (PBL) model based on constructivism in improving science learning outcomes of fourth grade students. The developed model integrates a PBL approach that focuses on contextual problem solving, constructivism theory that emphasizes active knowledge formation, and learning differentiation in content, process, and product aspects to accommodate differences in student learning styles. The research was conducted at SD Negeri 26 Membalong with 14 students (6 girls and 8 boys) as subjects in the 2025/2026 academic year. The method used was Classroom Action Research which included three stages: pre-cycle, cycle I, and cycle II. The results showed that the implementation of this model was effective and systematic. The average value of student learning outcomes increased from 58.6 in the pre-cycle to 76.4 in cycle I, and reached 92.9 in cycle II. This improvement indicates that the implementation of the Constructivism-Based Differentiated Problem-Based Learning (PBL) Model has a positive effect on improving the science learning outcomes of fourth-grade students. Thus, constructivism-based differentiated PBL has been proven to be able to create adaptive, meaningful learning and has the potential to improve students' cognitive learning outcomes.]]>
