ABSTRACT
An analysis of academic performance in reports at Kenya Certificate of Secondary Education (KCSE) has often indicated that performance in single sex secondary schools tends to be better than in mixed secondary schools .. This study investigated the environmental factors in coeducation at public secondary schools that affect leamers' performance. The environmental factors include gender ascribed roles that inhibited learners' achievements. The study also assessed the effects of coeducation on girls and boys learning behaviors in coeducation secondary schools. Both qualitative and quantitative data were adopted by use of Albert Social Cognitive Theory of Gender Development and Differentiation Findings dictate that single sex schools perform better than the co-educational schools. This reveals the need to enhance overall performance and general achievement of both boys and girls and particularly in mixed schools. It is recommended that more single sex schools should be established if performance in KCSE has to improve, and this may be the case nationally as well. The already existing coeducation schools should as an intervention create single sex classrooms p avoid distractions caused by the presence of the different sexes in the same class. This separation could enable teachers to reasonably address the gender differences that are associated ith either sex during the teaching and learning process.
