Appearances are deceptive, the saying goes. However, we devote much time to the presentation of ourselves, and ties and necklaces can take up more energy than other "substantial" matters. This article analyzes the history of the presentation of selves in schools through the study of school uniforms. It will be claimed that modernity configured a "regime of appearances" that had powerful effects on the ways that people relate to themselves and to others, and that schooling played a significant role in shaping it. The article will deal particularly with school uniforms as part of this regime of appearances, focusing on the development of vestimentary codes in Argentina and the United States of America. In Argentina, white smocks, which were adopted as the mandatory dress code around 1910 on the basis of an egalitarian rhetorics, were part of a politics of the body closely tied to Hygienism and linked to ideals of moral and racial purity. White smocks established a homogeneous and austere, monochromatic aesthetics of the school space that quickly identified transgression and indiscipline. In the US, uniforms were used for the schooling of minorities (Native Americans, women) as a way of rigorously training unruly bodies and of learning other aesthetic and bodily dispositions. Recently, urban public schools have adopted uniforms to counter-balance gangs' and rappers' dress codes. I believe that both cases show the fertility of analyzing school appearances for the history of school daily life and for understanding the effects that schooling produces in our societies.