The current literature on academic skill difficulties, whether considered as part of the continuum of ability or as a specific learning disability (LD), indicates that these problems often coexist with conduct problems and juvenile delinquency, and are risk factors for initial law-breaking behavior and for its persistence. However, less is understood about how this relationship develops. It is these broad questions that this project seeks to address. First, what is the causal pathway? Does LD cause delinquency, delinquency cause LD, or are both caused by something else? And can big data analytics applied to statewide datasets of information about juvenile justice (JJ) involvement help to answer this question? Second, as it is known that learning to read and do math (and thus becoming more employable) increases the likelihood of desistance (i.e., not committing any more illegal acts), what are the necessary parts of an intervention designed to teach these skills? And what role might technology play in such an intervention? To answer these questions, we will implement a study that includes two components, (a) a big data component and (b) an intervention component. For (a), we will work with a large historical dataset from the Harris County Juvenile Probation Department. For (b), we will work, in total, with 192 (48 per year) delinquent youth with severe LD in residential placement. These individuals, in a nonconcurrent multiple baseline design, will be offered an educational therapy designed to address severe reading problems in juvenile detainees using a novel mixed media intervention in which the person-to-person intensive 1:1 component is completed while youth are in residential settings (24 sessions, delivered in 90 minute settings 3 times a week) and a "gamified" educational smartphone learning tool follow-up completed upon release (with appropriate network fidelity monitoring and participant reinforcement). The person-to-person component is developed specifically for juvenile offenders with severe LD, combining two well-established and highly-regarded intervention programs designed to systematically build students' repertoire of grapheme-phoneme correspondence rules as well as develop comprehensive reading skills, from beginning reading to proficiency.