This paper is based on a recent study carried out as a part of the Visiting Research Fellowship at the UNICEF Office of Research. It offers a theoretical understanding of childhood poverty and educational exclusion, building on the empirical findings of the fieldwork carried out in Bangladesh to develop case studies addressing the questions, why do so many socio-economically disadvantaged children tend to drop out from formal secondary school, and why do some succeed? After exploring the challenges of childhood poverty and educational exclusion, it shows how the challenges could be mitigated through attention to the ecology of human development. This paper demonstrates a better understanding of childhood poverty and education in relation to the theoretical perspective through drawing together empirical evidence, summarising and interpreting it, in a more integrated manner and context. On the basis of this examination of the phenomenon, research findings have translated into recommendations for policy and practice to improve formal secondary schooling for socio-economically disadvantaged children in Bangladesh.