Final answer:
The primary influences for the development of physical education in America were societal changes, educational reforms, and the rise of professional and college sports.
Step-by-step explanation:
The primary influences for the development of physical education in America were a combination of societal changes, educational reforms, and the rise of professional and college sports.
Firstly, the increasing availability of leisure time and the rise of recreational activities such as sports and reading in the mid-20th century contributed to the demand for physical education in schools.
Secondly, educational reforms led by Horace Mann and other reformers in the 19th century emphasized the importance of education in preparing students for life, which included physical fitness and sports.
Lastly, the growth of professional and college sports, particularly in the late 19th and early 20th centuries, helped popularize physical activities and create a culture of sports in America.