The proposed study aims to investigate the effects of music training on the development of executive function skills (EF) in a population of school-age children, from under-resourced communities of Los Angeles. Executive function (EF) refers to a number of core cognitive capacities that allows the coordination of thoughts, decision making and planning. Development of these skills is increasingly recognized as an important contributor to well-being throughout the life span. There is particular interest in EF skills in children, given the considerable brain and cognitive developments associated with this period of life. Furthermore, low socio-economic status on its own may affect negatively the course of EF development. On the other hand, children from these disadvantaged communities have been shown to benefit the most from any intervention that has the potential to improve EF. Playing music is a task that engages many different brain regions; it requires the concurrent recruitment of distinct sensory and motor systems and their interplay with the attention and affective systems. Learning to play a musical instrument requires mastering abilities related to EF such as auditory working memory, motor inhibition and cognitive flexibility and has been suggested to benefit EF. Two groups will be recruited to participate in the proposed study: the experimental group will be monolingual, native English- speaking children, ages 9-11, from under-resourced communities of South and Central Los Angeles, who have had 2 years of music training with YOLA, a community-based free music education program. The comparison group will consist of children of the same age, from the same neighborhoods and socio-economic background, also monolingual, who did not have any previous experience of music training. Electrophysiological (EEG), neuroimaging (MRI) and behavioral probes will be used to assess the impact of music training on EF and its neural underpinnings. The findings from this study will provide answers to the ongoing discussion about music’s role in childhood education curricula, especially in underprivileged communities for whom access to private or out of school music education is limited, or none. By focusing on these communities, our findings will address a gap in the knowledge of child development and may serve to guide more effective public policies. In addition, under separate funding, we are evaluating the effects of music training, also with YOLA, in a bilingual child population from the same socio-economic background, using the same approach. We will compare the results from the two studies. Like music training, bilingualism has also been shown to have positive influence on EF development. However, it is not clear whether these two learning experiences influence EF similarly, or through distinct mechanisms. Comparison of the results obtained here in monolingual children with those obtained in the parallel bilingual group will allow the evaluation of the developmental effects of these two learning experiences. It will also allow the understanding of the differences, or similarities, of cognitive and brain development in children living in under-resourced urban communities.