“ Analysis of the Application of the Project-Based Learning Model in Improving the Mutual Cooperation Attitude of Primary School Students: Analisis Penerapan Model Pembelajaran Berbasis Proyek dalam Meningkatkan Sikap Gotong Royong Siswa Sekolah Dasar” (2026) Indonesian Journal of Education Methods Development, 21(1), p. 10.21070/ijemd.v21i1.1090. doi:10.21070/ijemd.v21i1.1090.