Deconstructing a conventional history class through tableau-vivant re-enactments, hacking interventions on text-books, or counter-exercises on memory and concept exploration, all con-ducted with the participation of teen-aged students, 'Margin of Error. How Do You Spell Wes-tern?' explores the traditional narratives on the Spanish Conquest of the New World as they are reflected in official texts used in schools in Spain and Latin America.