According to stereotype threat theory, the prospect of being judged in terms of a negative stereotype triggers underperformance (Steele, 1997; Steele & Aronson, 1995). Targets need not personally subscribe to the negative stereotype to be affected but must simply be aware that others may subscribe to it. The goal of this study was to investigate potential stereotype threat effects in an English as a second language (ESL) classroom. Participants were the 18 students in an ESL classroom at a Title I elementary school in Eastern, North Carolina. The study found that Latinx ESL students performed worse on an academic task when it was characterized as diagnostic of ability than when the same test was characterized as non-diagnostic of ability. They also experienced a higher level of anxiety and a higher level of orientation toward a performance-avoidance achievement goal. These effects seemed to be, at least in part, moderated by the participants' level of domain identification, such that the effects were specific to students who were more domain identified. The findings of this classroom investigation add to the extant literature by showing that Latinx ESL students may be susceptible to stereotype threat performance effects and that children who most highly value their performance may be most vulnerable. This small-scale exploration sets the stage for a larger study investigating the stereotype threat susceptibility of English language learners (ELLs).