Project OCCAMS (Online Consortium for Accelerating Middle School) developed and piloted an accelerated curriculum through a design-based research approach combining the Integrated Curriculum Model, principles of culturally responsive instructional design, and extensive compacting. The program created a pathway for diverse middle school students to complete a 3-year course of study in English Language Arts (ELA) in only 2 years and enter high school a year advanced of grade peers in language arts. Curricula were developed through collaboration of two university-based gifted education centers and a large urban school district. The program was designed primarily to serve students from subgroups underrepresented in gifted education who demonstrated advanced learning potential but did not yet meet state criteria for formal gifted identification. Evaluation data indicate participating students, as a group, made more rapid achievement gains in language arts than local comparison groups and equal to a comparison group of students formally identified as gifted participating in a regional talent search program. The use of a common online learning platform facilitated implementation by providing forums for collaboration and support among educators at multiple schools and universities and opportunities for continuous observation and data collection and allowed frequent iteration of the curriculum.