The Howard University Department of Systems and Computer Science proposes the Partnership for Early Engagement in Computer Science High School (PEECS-HS) program. This program partners Howard University with Washington, D.C. Public Schools (DCPS) and Google, Inc. to introduce a new course titled "Introduction to Computer Science (CS)" across DCPS high schools. The course will adopt and extend the Exploring Computer Science curriculum, originally piloted in the Los Angeles Unified School District (LAUSD). PEECS-HS will introduce students to the broad range of opportunities in CS, and allow them to develop basic competencies in CS fundamentals, and maintain a positive perception of CS. In addition, the program will produce a new unit on Mobile Application Development, which will be added to the general Exploring Computer Science curriculum. PEECS-HS will prepare in-service and pre-service DCPS teachers to teach the new curriculum. For sustainability, PEECS-HS will prepare in-service teachers to lead future Introduction to CS professional development sessions. As with many urban school districts, DCPS is predominately African-American, an important but often overlooked, component of the U.S. computing workforce. Many of these students exit or never enter the computing pipeline, in part because they often see CS as boring and unrelated to their interests. Introduction to CS aims to change those misperceptions. Adapting the Exploring Computer Science model to this environment will give further insight into mechanisms for attracting and retaining students from underrepresented populations in urban environments.