Most research on youth subordination and age inequality focuses on macrolevel institutions, ideologies, and discourses. While important, this macrolevel focus mystifies the ways in which young people themselves conceptualize and negotiate ageism. This article examines how adolescents collectively experience, politicize, and respond to ageism as they become active in educational justice and antiwar movements. Based on comparative ethnographic research with youth movement organizations in Portland, Oregon and Oakland, California, the author argues that adolescents' politicized understandings of ageism profoundly shape their social movement strategies. Furthermore, these understandings of ageism are rooted in young people's race and class social locations, and stand in relationship to social movement legacies. The divergent ways in which white, middle-class youth activists and young working-class activists of color collectively experience, interpret, and respond to ageism reveal the extent to which age inequality operates in conjunction with other systems of power and privilege.