The emerging field of urban ecology has the potential to engage urban youth in the practices of scientists by studying a locally relevant environmental problem. To this end, we are developing curriculum modules designed to engage students in learning science through the use of emerging information technology. In this paper, we describe the impact of one of the developed modules, urban bird bioacoustics, on students' understanding of sound. This module incorporates a technology-rich scientific investigation with traditional, well-established sound learning activities. Our findings suggest that while the investigation was successful, students' understandings of the properties of sound were mixed. These data suggest that instructional designers who are engaged in constructing a similar technology-enhanced curriculum should consider embedding their instructional support resources with appropriate student scaffolding questions, making explicit the connections between the investigation, technological tools and traditional science activities, and leveraging the multiple opportunities to learn content afforded by the technological tool. These findings will be used in next redesign of the curriculum materials. This work both shows how design-based research can be used to build knowledge about student scientific understanding and instructional and curricular design.