A major goal of science education reform is to produce curricula that improve the learning of all students. In this study, the authors explore the use of design-based learning (DBL) to achieve this end. They examined two middle school science classes taught by a teacher who switched for the first time from a standard, scripted inquiry approach to a DBL approach. The researchers were particularly interested in two questions. First, will students previously labeled high and low-achievers become equally engaged by DBL? Second, will the traditional gaps in science achievement associated with race/ethnicity, gender, and socio-economic status be increased or reduced? The findings presented two aspects of learning: engagement and achievement. Engagement has the potential to highlight students' performance in a way that standardized assessment methods do not reveal. The findings of this study suggest that DBL has the potential to increase students' desire to learn, enhance students' success