This study (1) reports Black girls experiences in urban mathematics classrooms and (2) makes an argument that those experiences point to broader discourses that serve as barriers to their positive mathematics identities. Forty-eight Black girls participated in focus groups that were collected as part of a longitudinal study that began when they were in pre-kindergarten. The girls experienced uncaring teachers, uninteresting curriculum, and unsupportive learning environments. Two new themes specific to mathematics learning emerged: a discourse of silencing and dismissiveness and a discourse of erasure of intellect. We propose a vision for disrupting these discourses.