Social or distributive justice refers to just distributions of income and wealth. Because social justice is an essentially contested concept, it has no true or core meaning, only several conflicting interpretations. This pluralism creates a problem for teachers who must explain to students how the various interpretations differ and underlie policy disputes. We propose that the plurality of interpretations can be understood as differences between a basic set of norms: equality, merit, contribution, effort, and choice. These norms are associated with familiar political ideologies. We illustrate each of these norms in a series of cartoons and suggest that moral opinions about the best norm result in irresolvable conflicts between the norms. We apply our theoretical analysis to these ideological conflicts in the policy areas of income, education, and discrimination in employment.