In seven studies, this research demonstrates that both the general public and educators may hold culturally‐shared, class stereotype‐laden mental representations that they reflexively use both to subjectively identify particular students as being high or low in academic ability, and determine who should receive educational support. Using procedures designed to capture people's mental images of others, we first observed that both the general public and aspiring educators mentally represent low‐ability students as qualitatively and quantitatively distinct from high‐ability students. Furthermore, the representations of low (vs. high) ability students captured from the public and aspiring educators were more likely to be associated with negative class‐based academic stereotypes by separate samples of the public and educators, such that a student who “looks” low in ability was also more likely to be labeled as being low‐SES, and having poorer academic motivation and work ethic. As a result, the low (vs. high) ability student was more likely to be denied college admissions or scholarship support by members of the American public and to be exposed to unsupportive instructional practices by teachers. Implications for our understanding of teacher biases are discussed.