The nineteenth-century dime novel was a significant component of adolescent culture. Dime novel Westerns prefigured emerging ideas of adolescence to inform cultural constructions of American boyhood. These texts articulated and responded to prevailing notions of proper and improper boyhood by imagining the frontier as a space of and for youth. Scholars have addressed many subversive elements of the dime novel, while largely ignoring how this literature interrogated hierarchies and categories of age. The present analysis explores that gap, highlighting the Western dime novel as a critical site for negotiating ideas of American boyhood in the late nineteenth century.