April 21 National Days

April 21 is the 111th day of the year (112th in leap years), with 254 days remaining in the 2025 calendar. Today marks 18 national and international days that span a wide range of themes—from education, conservation, and food traditions to language, wellness, and quirky celebrations. Some honor historic events or inventions, while others were created to raise awareness or simply bring a little fun into everyday life.

National and International Days on April 21

Advisor Appreciation Day: This day honors the educational advisors who guide students through academic decisions, career planning, and life choices. From helping with college applications to offering course selection advice, these advisors play a vital role in student success. April 21 recognizes their dedication and the impact they have on shaping futures.

Big Word Day: This lighthearted holiday celebrates the use of long, impressive vocabulary. It encourages people to swap out short words for more substantial ones and play with language in fun and intelligent ways. It’s not just about sounding smart—it’s also a celebration of the richness of language and expression.

International Hemp Day: Hemp has been cultivated for millennia for uses ranging from textiles and rope to biodegradable plastics and nutritious food. International Hemp Day brings attention to the plant’s versatility and encourages awareness of its environmental benefits. The day also distinguishes hemp from its psychoactive cousin, marijuana, and promotes sustainable practices using hemp.

➡️ A similar day, National Hemp Day, is celebrated on February 4.

International Loch Ness Monster Day: Celebrated each year on April 21, this date marks the anniversary of the famous “Surgeon’s Photograph” of Nessie, taken in 1934. While many of the monster sightings remain unproven, the fascination endures. The day celebrates Scotland’s most legendary lake creature and the folklore that continues to surround it.

Keep Off the Grass Day: Reminds everyone to protect and preserve their lawns by staying off them, especially during critical growing seasons. Started in 2013 by writer Jace Shoemaker-Galloway, the day emphasizes that excessive foot traffic damages grass, weakens its root systems, and makes it harder for healthy growth. The goal is to keep green spaces beautiful, environmentally beneficial, and thriving for everyone to enjoy.

National Bulldogs Are Beautiful Day: Founded in 2007 by author Jackie Valent, this day challenges narrow definitions of beauty by spotlighting the lovable charm of bulldogs. Inspired by her book Stinky the Bulldog, Valent created the day to promote acceptance and raise awareness about bulldog care and adoption.

🐾 For more dogs, cats, and pets national days, visit the dedicated pages or use the search feature on our website to find exactly what you’re looking for!

National Chickpea Day: Chickpeas have been cultivated for more than 9,000 years and are used in countless cuisines across the globe. From hummus and falafel to curries and salads, this humble legume gets its moment of appreciation on April 21. It’s a celebration of flavor, nutrition, and history.

National Chocolate-Covered Cashews Day: This food holiday brings attention to a perfect pairing—creamy chocolate and crunchy cashews. Originally native to Brazil, the cashew tree now grows in many tropical areas. The blend of sweet and salty makes this treat a fan favorite.

🌰 A related day, National Cashew Day, is celebrated on November 23rd. Other nut-related days are National Almond Day and Grab Some Nuts Day.

National Kindergarten Day: Honoring the birth of Friedrich Froebel (April 21, 1782), this day celebrates the invention of kindergarten. Froebel opened the first kindergarten in Germany in 1837, emphasizing learning through play. The U.S. adopted the model later, with the first kindergarten opening in Wisconsin in 1856.

National Pet CBD Day: Observed on April 21, this day highlights the potential benefits of cannabidiol (CBD) for pets, particularly dogs. While still being researched, CBD is used to support pets with conditions like anxiety, pain, and seizures. The day aims to promote safe and responsible usage.

National Rendering Day: Started by the North American Renderers Association, this day promotes the practice of rendering—transforming inedible animal parts and used cooking oil into new materials. Celebrated near Earth Day, it highlights the environmental benefits of reducing waste and reusing resources.

National Surprise Drug Test Day: Created as a humorous (and unofficial) follow-up to April 20, National Marijuana Day, this observance gained traction through social media. The idea is simple: after a day commonly associated with cannabis use, April 21 reminds people—especially employees—that surprise drug tests are a possibility. While no official organization claims credit for the day, it’s widely recognized online.

National Tea Day 🇬🇧: Founded in 2016 in the United Kingdom to coincide with Queen Elizabeth II’s birthday, National Tea Day celebrates the cultural and social importance of tea. The day has since become a vibrant celebration across the UK, complete with events, tastings, and themed promotions. While there are other tea days globally, April 21 is the one most associated with British tea traditions.

National Yellow Bat Day: Commemorates the activation of the 265th Army Security Agency Company (Airborne) on April 21, 1967. The unit served with the 101st Airborne Division and used a yellow bat as its symbol—representing secrecy, night operations, and intelligence work. The insignia featured a bat with outstretched wings over a rising moon and the motto “Through the Night.” In 2016, Doug Bonnot, President of the Sentinel Chapter of the 101st Airborne Association, helped establish the day to honor the history and service of this elite unit.

Thank You for Libraries Day: Celebrated each year on April 21, this day honors libraries and the important role they play in education, literacy, and community life. With more than 110,000 libraries across the U.S., these institutions provide resources, access to information, and safe public spaces for learning and discovery.

Tuna Rights Day: Observed to raise awareness about sustainable tuna fishing and the importance of protecting marine ecosystems, Tuna Rights Day calls attention to the overfishing of key tuna species. From skipjack to bluefin, many types of tuna are now endangered or heavily exploited. This day promotes responsible consumption and better fisheries management.

World Creativity and Innovation Day: Proposed by Marci Segal in 2001 and adopted by the United Nations in 2018, this day encourages people worldwide to use creativity to solve problems and improve their communities. It’s also tied to the UN’s Sustainable Development Goals and recognizes innovation across all fields—from science to the arts.

World Curlew Day: Founded in 2017 by Mary Colwell, this grassroots initiative aims to raise awareness about curlews, a group of birds threatened by habitat loss and climate change. April 21 was chosen because it marked the start of Colwell’s 500-mile walk across the UK to draw attention to their plight. Today, the day is promoted by Curlew Action and includes outreach, education, and conservation programs.