American Secular Holidays Calendar
Calculates secular dates for any year for U.S. federal holidays, current trading holidays, and other celebrated observances.
Find facts and lesson plans about Constitution Day, the American holiday commemorating the signing of the United States Constitution. Observed on September 17th.
USA.gov: American Holidays
Official information from the U.S. government about holidays celebrated in America, including federal holidays, secular, religious, and international holidays.