Study aim As mentioned earlier, ECCE research is a relatively new phenomenon, and there is little evidence regarding how effective Chilean ECCE programs are. The present study aims to address this need by estimating the long-term effects of public ECCE program son students’ academic achievements. An ideal evaluation would assess an early childhood program’s contributions to later academic achievement by comparing two identical individuals, one who received a treatment and one who did not, and observe their outcome differences over time. More specifically, we are interested in the counter factual, i.e., what would have happened to the child without preschool if he/she had received the preschool treatment.Ideally, we would construct a true experiment, such as the one carried out to assess the impact of the Perry Preschool study and the Abecedarian projects (Barnett, 1995; Campbell et al., 2001). How-ever, experimental designs are not always possible, as they are costly and complicated especially when trying to assess the effects of large-scale public programs tailored to all low SES children.When experiments are not possible expostfac to, well constructed and implemented quasi-experimental designs are the second best option (Gelman & Hill, 2007). The present study addresses the question: are public ECCE programs in Chile an effective educational tool to enhance the academic performance of children from low-income backgrounds, helping thereby to bridge the achievement gap among children from different socioeconomic groups?