From the perspectives of Graduate Research Assistants (GRAs), this study examines the design and implementation of a simulated teaching environment in Second Life (SL) for prospective teachers to teach algebra for diverse learners. Drawing upon the Learning-for-Use framework, the analyses provide evidence on the development of student avatars in construction and role-playing activities. The study reveals challenges, procedures, and suggestions for future simulations. This study also calls for research efforts toward preparing mathematics teachers for cultural diversity. Ma, T., Brown, I., Kulm, G., Davis, T. J., &; Allen, D. (2014). Constructing and Role-Playing Student Avatars in a Simulation of Teaching Algebra for Diverse Learners. Urban Education. doi: 10.1177/0042085914542658