<p>This qualitative case study investigates the extent to which constructivist learning principles are implemented in actual classroom practices in Ethiopia. Grounded in the theoretical frameworks of Piaget and Vygotsky, the study examines the alignment between national education policies, curriculum frameworks, and textbooks, and how these are reflected in classroom instruction in Science, Mathematics, and English. Data were collected through classroom observations, unstructured interviews with nine teachers, and document analysis of national policies and curriculum materials. Findings revealed a significant disconnect between policy aspirations and teaching practices. While official frameworks advocate for active, student-centered, and inquiry-based learning, classroom instruction remains predominantly teacher-centered, with limited evidence of collaborative learning, reflective thinking, or real-world application. Large class size, insufficient instructional materials, content-time in-balance, and a lack of practical teacher training in constructivist pedagogy were found as constraining factors. The study underscores the need for sustained professional development programs, curriculum streamlining, and systemic support to enable effective implementation of constructivist approaches in resource-constrained school environments. These findings contribute to the discourse on educational reform in developing countries and offer actionable insights for policymakers, curriculum designers, and teacher educators committed to enhancing authentic and constructive teaching and learning quality.</p>