Decision-making in children and teens has been receiving growing attention in recent years. This interest stems from the need to design interventions in schools in order to improve opportunities and outcomes later in life. It also stems from the realization that understanding developmental trajectories of decision-making helps understanding adult behavior. Throughout development, we experience radical biological changes that shape the way we process information and make decisions. The LILA study provides a unique account of changes in preferences and strategic behavior during development. Several lab-in-the field experiments conducted at LILA, a K to 12th grade school in Los Angeles, reveal how students develop abilities to choose consistently within domains, plan ahead, backward induct and best respond and how the development of these abilities track the known development of executive functions, cognition and logic.