Why Were American High School Students Supposed to Study Geometry in the Twentieth Century?
Abstract This study contributes to the historical examination of the justification question for the particular case of the high school geometry course in the United States. The 20th century saw the emergence of competing arguments to justify the geometry course. Four modal arguments are identified including that geometry provides an opportunity for students to learn logic, that it helps develop mathematical intuition, that it affords students experiences that resemble the activity of the mathematician, and that it allows connections to the real world. Those arguments help understand what is put at stake by the various kinds of mathematical work that one can observe in contemporary geometry classes. The underlying assumptions of those arguments also help locate the influences in contemporary reform movements with regard to the study of geometry.
