After launching an online Computer Science post-baccalaureate degree program, this study was undertaken to inform the redesign of an introductory Computer Science course using a student-centered, problem-based learning approach. The research team proposed a weekly/unit learning trajectory as they were engaged in student-centered, problem-based learning. Over a timeframe of three university terms, the research team used a design-based, iterative examination to refine the implementation of various instructional actions in the learning trajectory. Multiple small groups of students discussed their learning experiences each term, providing directions for improvements. The analysis directed successive iterations, refining the content, problem solving, and collaborations in the class. This research method assured authentic student voice in an iterative redesign of the course.