How and why students develop productive science learning identities is a key issue for the education community (see Bell et al, 2009). Carlone, Scott, and Lowder describe the changes in the science identities of three students as they move from fourth to sixth grade. The authors discuss the processes — heavily mediated by race, class, and gender — by which the students position themselves, or are positioned by others, as being more or less competent learners in science.