Abstract
Studies have consistently attributed students' poor achievement in physics to the continued use of conventional teacher-centred instructional approaches. This study, therefore, investigated the effect of a contextually responsive, cognitively guided instructional strategy on the academic achievement of secondary school physics students in Ibadan Metropolis, Nigeria. The interaction impact of students' mathematical ability was also assessed. Grounded in theory of constructivism, the study adopted the quasi-experimental pretest-posttest control group design. The research spanned 13 weeks and involved 110 senior secondary school physics students. Validated research instruments were used for data collection, and data were analysed using multilevel linear modelling. Findings revealed that a significant impact of the intervention on the students' academic achievement, F(1, 850.810) = 137.668, p < 0.001. Further analysis indicated substantial differences in post-test mean achievement scores between students exposed cognitively guided instructional strategy and those taught with the conventional method. The study recommends the adoption of instructional contextualisation as an effective pedagogical approach for teaching physics. It also suggests further research into the interaction effects of additional learner-related variables on students' academic performance in physics.