This paper addresses a central need among people who are blind, access to inquiry-based science learning materials, which are addressed by few other learning environments that use assistive technologies. In this study, we investigated ways in which learning environments based on sound mediation can support science learning by blind people. We used NetLogo, a multi-agent programmable modeling environment that is widely used for learning about complex systems. In order to provide blind people with access to such models, we used a component that supports sound-based mediation. The sound-based mediation provided real-time information regarding objects' speed, location, and interactions with other objects. We examined blind people's learning about a chemical system of contained gas particles. The study employs a pre-test intervention-post-test design. Four adults participated individually in the study. They achieved most referent-representation connections; their scientific conceptual knowledge became more specific and aligned with scientific knowledge; and their systems reasoning showed greater discrimination and relation between components. Discussion addresses learning with sound-based mediation in broader terms and suggests further research into the potential of this unique type of low-cost learning environment to assist blind people in their science learning. (Contains 1 note, 2 tables, and 5 figures.)