Dissertation (MA Education)The purpose of this study was to establish appropriate strategies for enhancing students’ competencies in environmental management during the teaching and learning process in secondary school in Tanzania. The study employed a Gradual Release of Responsibility (GRR) model in which teachers’ and students’ responsibilities were defined clearly to shape the Environmental Instructional Lesson materials (ELM). The sample population involved ten (10) Geography teachers, thirty-two (32) students, twenty (20) community members, two (2) environmental experts and two (2) lecturers located Dodoma Region. The study employed a mixed approach integrating both the qualitative and quantitative aspects in designing, implementation, assessment and evaluation of the instructional materials developed for enhancing students’ competences in environmental management. An exploratory sequential study was used in designing the ELMs from research data. Data analysis was done through thematic analysis for qualitative data and descriptive analysis for quantitative data. Research data were gathered through different methods such as interviews, document analysis and classroom observations. The findings from the study indicates that the most prevailing environmental problems perceived by the involved society are deforestation, soil erosion and mismanagement of wastes. The study revealed number of challenges teachers face in teaching and learning environmental problems, includes shortage of teaching and learning materials, lack of in-service training and lack of support from other education stakeholder in integrating the most prevailing environmental problems during the teaching and learning process. Moreover, the findings indicate that, the active involvement of teachers and experts in the development of the lesson materials lead to the establishment of materials that assessed to be effective to enhance students’ competences in environmental education. The mean was 30.63 and the standard deviation was 5.19 during post-test which indicate that the students’ competences in environmental management was developed. Finally, the study recommends that it important to consider society priorities in instructional lesson materials by collaborating with other education stakeholder to ensure effectiveness in designing and implementation of curriculum materials