The article is an example of a still rare study of the politics of ethnicity in the contemporary Russian school. It focuses on the stereotypical thinking of St. Petersburg teachers confronting such phenomena as new ethnic differentiation of the student body, ethnic migrations, and the collapse of the Soviet nationality policy. In this new sociopolitical and professional situation, ethnic stereotyping becomes an instrument of self-orientation for the teachers. Being an important institute of population homogenization and reproduction of the dominant discourses, the school acts as a model of power-relations in contemporary Russian society. The author’s goal is to deconstruct the semantics of the teachers’ language of otherness; their understanding of the Russianness and foreigness; the status of the Russian language, religion, “culture”, history, family patterns in these constructions; etc. The analysis is based on problem-oriented interviews conducted in 2002–2004 in fifteen public schools in St. Petersburg. The author concludes that contrary to the actual low social and economic prestige of their profession, public schools teachers participate in the (re)production of the dominant discourse defining the limits of culture and non-culture, political participation and non-participation. This discourse is not self-reflective and well-defined; it refers to the old Soviet values hierarchy based on a high status of “culture” in society. At the same time, this discourse reflects current phobias produced by the crisis of the “national idea,” the failure to deal with labor migration, the economic competition that it produces, and so on. Petersburg teachers are troubled by the academic success of their non-Russian students that opens their path for successful social mobility. Through national stereotyping these non-Russian students are marked as a lower social group that cannot pretend to share cultural capital with Russians. At the same time, the teachers lack real instruments of power because their own social capital was dramatically devaluated during the 1990s.