gozim, Mohamed, and Djamila Hermez. 2021. “the Effectiveness of the Differentiated Education Strategy in Teaching Mathematical Concepts to Educationally Retarded Pupilsin the First-Grade School ”. Al-Jamie Journal In Psychological Studies and Educational Sciences 6 (1):353-72. https://journals.univ-msila.dz/index.php/ajpe/article/view/9461.