The prevailing image of twentieth-century English “youth” is as a triumphal signifier of affluent leisure consumption. By contrast, this article demonstrates the importance of young working-class people's economic role as wage-earners in the mid-twentieth century. This shaped their treatment by the family and the state and the life histories of the adults they became. Juveniles were crucial breadwinners in interwar working-class households. However, the consequences of high unemployment among adult males helped redefine youth as a period of state protection and leisure in the post-1945 decades. Nevertheless, personal affluence remained limited, and young people's economic responsibilities high, until at least the mid-1950s. The history of twentieth-century youth is best understood as one in which young working-class people's fortunes were closely linked to their family's circumstances and their importance as a supply of cheap labour. Social class thus formed, and was formed by, the experience and memory of being young.