The purpose of this paper is to build a dynamic structural model of educational choices in which cognitive skills shape decisions. The model is estimated by maximum likelihood using cohort data where individuals are observed from birth to the middle of their working life. These data are unique in that they include cognitive skills test scores collected as early as age 7. We then investigate how alternative policies foster educational enrolment. In particular, we simulate the effect of two subsidies different in the timing of disbursement. The first consists of grants assigned directly to individuals aged between 16 and 18. The second is assigned to the parents earlier on, when the cohort is still in its childhood. The latter subsidy affects cognitive skills accumulation and in turn educational choices. Our results suggest that a grant fosters enrolment at the lowest cost but the parental income subsidy generates more welfare as measured by a class of social welfare functions. Nevertheless, these differences in costs and welfare are small. Overall, the results reinforce the view that government investments in cognitive skill accumulation during childhood are worthwhile. However, the results also indicate that such investments should be well structured to ensure a high return.