This paper draws together research on seasonality, child labour and education in the context of primary education in sub-Saharan Africa. It describes how income poverty and demand for labour can fluctuate within and between years, affecting participation and progression through school systems. It highlights how analysis of the private and public costs of education frequently ignore the significance of seasonal patterns related to the agricultural cycle and migration. It argues that education policy and practice should be more clearly articulated with fluctuations in household income, demand for labour (especially school age children), and seasonal migration cycles. Educational reforms to improve school enrolment and lessen the burden of education on poor will not succeed unless seasonality is recognised. (Contains 2 tables, 18 figures, and 18 footnotes.)