<p>Constructivist approaches in education prioritise learner-centred activities in which students construct knowledge through experiences and reflections. These methods emphasise active participation, collaboration, and problem-solving, aligning with modern educational goals that promote critical thinking and learner autonomy. However, its implementation in primary school classrooms faces various challenges. This study explored the challenges faced by Fijian primary school teachers in implementing constructivist approaches in their classrooms. A mixed-methods research design was employed, involving semi-structured interviews with 12 Year 8 teachers and a questionnaire administered to 68 Year 8 teachers. The findings revealed key barriers, including large class sizes, lack of resources, time constraints, rigid curricula, limited teacher education, student readiness issues, assessment pressures, and classroom management difficulties. This study highlights the need for systemic changes in educational policies, enhanced teacher-education programs, and better resource allocation to support the effective implementation of constructivist approaches in Fijian classrooms. </p>