In this project, we study the effects of "Hogares Comunitarios", a large nutrition and childcare programme in rural Colombia. The intervention we study is a community nursery programme that provides nutrition and child care for the children of poor households. The evaluation of this program is challenging because children from more disadvantaged backgrounds are the ones that tend to enrol in the program. Naive evaluation strategies would estimate that the programme has null or negative effect on child nutrition. We consider an instrumental variable strategy to estimate the impact of the programme, using distance from the household to the nearest nursery and the fee paid in the municipality as instrumental variables.