Saragarhi Day (Sikhism) Patriot Day (United States) Second Saturday Day of the Workers in the Oil, Gas, Power, and Geological Industry (Turkmenistan) Saturday after first Monday Carl Garner Federal Lands Cleanup Day (United States) Second Sunday Auditor's Day (Church of Scientology) Father's Day (Latvia) National Grandparents' Day (Canada, Estonia) Tanker's Day (Russia) Turkmen Bakhshi Day (Turkmenistan) First Sunday after first Monday National Grandparents' Day (United States) Week of September 17 Celebrate Freedom Week (Kansas and Texas, United States) Third Tuesday Prinsjesdag (Netherlands) September 17 but observed on previous Friday if it falls on a Saturday or following Monday if on a Sunday Constitution Day (United States) Third Friday National POW/MIA Recognition Day (United States) Third Saturday National Cleanup Day (United States) Oktoberfest celebrations begin (German diaspora, local dates may vary) Software Freedom Day (International observance) Weekend of the week of September 17 Von Steuben Day (United States) Third Sunday Day of the Walloon Region (Wallonia, Belgium) Father's Day (Ukraine) Federal Day of Thanksgiving, Repentance and Prayer (Switzerland) Warachikuy (Cusco, Peru) Week of Sunday before September 23 Bisexual Awareness Week Week of September 22 Tolkien Week Last week Banned Books Week (International observance): Last full week National Forest Week (Canada) National Tree Day (Wednesday of last full week): Celebrate Freedom Week (Arkansas and Florida, United States) Third Monday Respect for the Aged Day (Japan) Observances pertaining to the September Equinox Autumnal Equinox Day (Japan) French Republican New Year. (defunct) Guldize (Cornish people) Higan (Japan) Mabon (Neopaganism, Northern Hemisphere) Miķeļi (Latvia) Ostara (Neopaganism, Southern Hemisphere) Fourth Friday Native American Day (California, United States) Last Friday Manit Day (Marshall Islands) Last Saturday Girls in Aviation Day (International observance) National Public Lands Day (United States) Last Sunday Daylight saving time begins (New Zealand) Gold Star Mother's Day (United States) Fourth Monday American Indian Day (Tennessee, United States) September Declaration (Flanders, Belgium) Last Wednesday Maple Leaf Day (Canada) Last weekday in September Ask a Stupid Question Day (India, United Kingdom, United States) Fixed Gregorian observances September 1 Anniversary of the Start of the Armed Struggle (Eritrea) Constitution Day (Slovakia) Disaster Prevention Day (Japan) Emma Nutt Day (International observance) First day of school in many countries in Asia, Europe and the Americas. Flag Day (Honduras) Independence Day (Uzbekistan) Journalist Day (Taiwan) Knowledge Day (Russia, Ukraine and Armenia) National Cherry Popover Day (United States) Random Acts of Kindness Day (New Zealand) Start of National Arbor Week (South