In this work we examine youth learning in an informal computing program implemented through a library-university partnership. In particular, we introduce and illustrate a culturally responsive computing framework which served as a foundation for the design of the program. Subsequently, we examine youth collaboration as well as affective and cognitive learning outcomes. Data were collected from university program facilitators and 30 youth over one semester. Data were collected through observations, lesson plans, computational artifacts and interviews with two case study youth. Results indicated that youth formed a variety of learning communities during the collaborative development of computing artifacts. Frequent participants were found to work with a greater number of peers compared to less frequent participants. Results from case study participants also indicated improvements in their computational competencies. Findings from this work have implications for the design of informal learning environments that help broaden participation in computing.