It is widely held that work by children obstructs schooling, so that working children in impoverished families will find it difficult to escape poverty. If children's school attendance and work were highly substitutable activities, it would be advisable to quell work in the interest of schooling and, if less child work were desirable for its own sake, to boost school attendance so as to reduce child work. Hence, this article examines the effects of schooling costs upon both children's propensities to work and to attend school in rural northern India in a bid to assess the extent of trade-off between the activities. Analyses of data from Uttar Pradesh and Bihar, two Northern Indian states, reveal a positive relation between child work and schooling costs, a negative relation between school enrollment and schooling costs, and that the decrease in the probability of child work from a decrease in schooling costs is comparable in magnitude to the corresponding increase in the probability of school enrollment, implying children's work and school attendance are strongly substitutable activities. Thus, unlike recent studies of child work in India's South Asian neighbors of Bangladesh and Pakistan, this paper uncovers evidence of substantial trade-off between child work and school attendance.