The aim of this study was to reconsider the history of the US high school physics in the early 20th century. The authors analyzed the historical change of the purposes of the US high school natural philosophy and physics between 1821–1930. This period was divided into three sub-periods, and the purposes of the subjects found in each sub-period were analyzed by the frameworks used in Osborne’s arguments on four values of science education: Economic, Democratic, Cultural, and Utilitarian. As a result, the purposes of natural philosophy and physics changed as shown below:
1. Development of citizens who have a religious understanding of nature in the first sub-period (1821–1872).
2. Mental discipline for both students who become future citizens and ones who study physics in college in the second sub-period (1873–1899).
3. Development of citizens who understand the history of physics and adopt scientific habits of mind in the third sub-period (1900–1930).
While high school physics in the early 20th century was regarded as a subject for the preparation for further scientific study in college, this study found that it was oriented toward democratic and cultural purposes.