Lower vocabulary in German is repeatedly reported for students with Turkish migration background attending school in Germany. We investigated whether in students of Turkish descent (a) learning vocabulary is impaired when the teacher activates the negative stereotype that students with Turkish family language learn less well and (b) whether a Turkish-origin teacher, as an ingroup expert model, can mitigate negative effects of the activation of the stereotype. In an experimental study, Turkish- and German-origin students (N = 182) living in Germany worked individually on a tablet on a vocabulary learning task instructed by a teacher in a video tutorial who introduced herself with either a Turkish or German name. Before the task, the teacher either mentioned that students in general (no stereotype activation) or students who speak Turkish in their families (stereotype activation) often have difficulties acquiring new vocabulary. A multiple-group regression analysis showed that Turkish-origin students learned significantly more under stereotype activation with the Turkish-origin teacher than in all other conditions. Results suggest that students are particularly motivated to learn when the teacher represents their ingroup targeted by negative stereotypes and openly addresses potential difficulties students of the stigmatized ingroup may encounter. We discuss the findings in light of the literature on stereotype threat and on the role of ingroup expert models.