From the NHS Website (https://www.nhs.us/about/):
The National Honor Society (NHS) is the nation’s premier organization established to recognize outstanding high school students. More than just an honor roll, NHS serves to recognize those students who have demonstrated excellence in the areas of scholarship, service, leadership, and character. These characteristics have been associated with membership in the organization since its beginning in 1921.
Today, it is estimated that more than one million students participate in NHS activities. NHS chapters are found in all 50 states, the District of Columbia, Puerto Rico, many U.S. territories, and Canada. Chapter membership not only recognizes students for their accomplishments, but challenges them to develop further through active involvement in school activities and community service.
The National Association of Secondary School Principals (NASSP) officially established NHS in 1921. Though many local and regional honor societies existed prior to 1921, no nationwide organization had been founded. Under the leadership of Dr. Edward Rynearson, principal of the Fifth Avenue High School in Pittsburgh, the organization grew from the original Alpha Chapter at the Fifth Avenue School to more than 1,000 chapters by 1930. Equipped with a constitution, an emblem and motto, and a group of dedicated principals as coordinators, the new NHS organization quickly developed into one of the country’s leading educational groups.
Four main purposes have guided chapters of NHS from the beginning: to create enthusiasm for scholarship; to stimulate a desire to render service; to promote leadership; and to develop character in the students of secondary schools. These purposes also translate into the criteria used for membership selection in each local chapter.