Where the World Gathers to Celebrate Every Day




One of America’s favorites, National Double Cheeseburger Day recognizes a food icon savored across the United States. 

Hamburger.  Seasoned ground beef, grilled and placed between two slices of bread or a bun. Top with sauteed onions, peppers, pickles, sliced onions, and cheese. Add condiments such as ketchup, mustard, or mayo. Any one of these combinations would create a modern American version a hamburger.

Now, double the patties and the cheese. The celebration requires it.

While the day is about the double cheeseburger, that doesn’t mean you can’t add your favorite toppings. When it comes to adding some tanginess to a burger, a few ingredients never fail. Goat cheese brightens a burger every time. But if you’re looking for a crispness, too, add some creamy coleslaw instead. Another option in this category is the reliable tartar sauce.

If you like to bring the heat, you can look to your cheeses. Pepper jack is a mild way of adding some spice. However, if you prefer to test the limits, fresh sliced jalapenos or habaneros will also do the trick.

It is most likely that the hamburger sandwich first appeared in the 19th or early 20th centuries, but there is much controversy over its origin. Over the years, the hamburger has become a culinary icon in the United States.

And Americans love their burgers! Restaurants dedicated to making them just right have been in business for generations. Even those who refrain from red meat don’t hesitate to find a way to enjoy a juicy burger. Whether the burger is charbroiled, grilled or barely kisses the heat, there’s a flavor for you.

So when something this delicious exists, double it! Then celebrate it!

HOW TO OBSERVE #DoubleCheeseburgerDay

Enjoy a delicious double cheeseburger. Add your favorite toppings. Since it’s a celebration, be sure to invite friends to join you. Whether you cook together or go out to eat, remember to #CelebrateEveryDay and share your meal using #DoubleCheeseburgerDay to post on social media.


We were unable to determine the origin of National Double Cheeseburger Day.



On September 15th, National Online Learning Day recognizes the advantages and vast potential of online learning. It also honors the accomplishments of online students everywhere.

Whether you’ve ever taken an online course, used educational resources at a traditional brick-and-mortar school, or taught them, this day is for you! The day showcases online learning helping people accomplish their goals and dreams. It helps check things off their bucket list!

Not only that, but online learning offers valuable resources to parents, too. The ability to check in with teachers and assist their children remotely heightens the educational experience.

Alexandra is excelling at school and her self-esteem is sky high. She believes in herself as a student and can be herself. We also love online learning for the rigorous curriculum and we know that Alexandra will be prepared for her future and career. ~ Emerald Zeitz – parent of an online student

Evolving online technology makes education more manageable and convenient. Every day, students earn high school diplomas, certificates, college degrees, and credits online. Online Learning Day brings national recognition to these students. And online schooling continues to grow and provide new resources and support to students.

The observance is about students learning, educators teaching, and family members supporting this type of education. With your selfies and other photos, the goal is to cultivate blended and online learning and recognize the student possibilities available with this type of education. Become part of the national online community on Online Learning Day! The power of technology has knocked down barriers and built bridges in education. With online learning, adult students can balance working with furthering their knowledge, and today’s youth can receive an individualized education and learning environment.

HOW TO OBSERVE #OnlineLearningDay

Show your support for online students everywhere by participating! If you’re an online student or educator, know that your academic achievements have made this celebration possible. On September 15th share what online learning has taught you.

On your existing social media channels using #OnlineLearningDay and this statement, “Online Learning has taught me to _______!” Fill in the blank and then tag three friends to continue the celebration. (Students, please note, you must be over the age of 13 and have your parents’ permission.)

Join the conversation on Facebook, Facebook Event, Twitter, and Instagram.


National Online Learning Day was established in July of 2016. It recognizes the online education community with an official day focusing on the significant achievements made through online schooling and the students attending.

The Registrar at National Day Calendar proclaimed the observance to be observed on September 15th annually.



National Tackle Kids Cancer Day on September 15th gives you a chance to be part of the cure for pediatric cancer research. Join other Tackle Kids Cancer supporters by volunteering to rally our community and raise the needed funds for pediatric cancer research. Did you know only 4% of federal cancer dollars apply to pediatric cancer research? Finding a cure means more than ever. Tackle Kids Cancer Day gives us a platform for our voices to be heard. Help find a cure for pediatric cancer.

The day supports innovative research and patient care programs at the Children’s Cancer Institute (CCI) at Hackensack University Medical Center. CCI is pioneering over a dozen clinical trials to treat aggressive types of pediatric cancer. Most notably, their extensive pediatric neuro-oncology program is leading the way to establish new protocols in treating this dire diagnosis.  Additionally, Tackle Kids Cancer funds the Cure and Beyond Program – one of a handful of survivorship programs for pediatric cancer survivors in the country.

On Tackle Kids Cancer Day, let your support shine through! Gear up and help find a cure for pediatric cancer!

HOW TO OBSERVE #TackleKidsCancerDay

Show your support by joining the team in several ways.

  • Donate! Your donations support several programs, research and pave the way to a cure.
  • Support essential clinical care, unique support services, and groundbreaking cancer research needed to find a cure.
  • Get involved by organizing a fundraiser or volunteering for an event.
  • Share your experiences as a survivor, parent, or researcher. Your stories inspire understanding and support.

As you join the celebration, be sure to share by using #TackleKidsCancerDay to share on social media.


Hackensack University Medical Center Foundation founded National Tackle Kids Cancer Day to raise awareness about pediatric cancer. More research and fundraising supports finding a cure for this horrific disease. Tackle Kids Cancer formed in September of 2015, and since its inception, it has raised $4.5 million from nearly 7,000 supporters. The funds go toward pediatric cancer research occurring at the Children’s Cancer Institute at Hackensack University Medical Center. As one of the fastest-growing philanthropies in the country, Tackle Kids Cancer has supporters from all 50 states and over a dozen countries.

The Registrar at National Day Calendar proclaimed the day to be annually observed starting in 2017.

GREENPEACE DAY - September 15


Greenpeace Day is observed on September 15th commemorates the movement that began on this day. 

This day highlights activism in the name of the environment. The day recognizes peaceful protest for change to improve air quality, reduce reliance on fossil fuels, use of plastics, water quality. Conservation and preservation fall under their topics of environmental justice.

activist | NOUN

ac·tiv·ist /’aktivest/ a person who takes part in actions intended to achieve political or social change; may be an individual or member of an organization

Founded in 1971 by 17 activists protesting nuclear testing off the shores of Alaska, Greenpeace now boasts a worldwide membership. Taking on environmental issues and raising awareness, their campaigns continually strive to support and preserve the Earth.

HOW TO OBSERVE #Greenpeace Day

Learn more about activism. Find out about the roots and how its influence has changed the world around you. Give a shout-out to an organization that is supporting the environment. Share your experiences, too. You can also volunteer and use your voice. Take action and support vital change. 

And while you’re celebrating, use #GreenpeaceDay to post on social media.

When is Earth Day?


Greenpeace was founded on September 15, 1971, when 17 activists set sail on the Phyllis Cormack. They hoped to stop the nuclear testing about to take place off the shores of Alaska. While the testing proceeded, the protest set in motion a movement still growing today. In honor of Greenpeace, Vancouver Mayor, Gregor Robertson proclaimed Greenpeace Day in 2011.



On September 15th, National Linguine Day fills the dinner menu at home and restaurants across the country. 

From the Liguria region of Italy, linguine means “little tongues” in Italian. Made from durum semolina flour, linguine is one of the world’s oldest kinds of pasta. Fettuccine and linguine both developed around 400 years ago. While both are thin, flat noodles, linguine is narrower and more elliptical in shape. As a result, linguine produces a more delicate pasta. To avoid breakage, pair linguine with thinner, lighter sauces.

However, lighter sauces don’t limit linguine’s flavor profile. In fact, linguine recipes offer a wide variety of sauces. Whether you prefer spicy pasta or seafood, linguine offers a nice base. It compliments herb and butter sauces nicely, too. When adding fresh vegetables, linguine allows the bright colors to shine. Pesto lovers rave over linguine. Another ingredient that favors linguine is earthy mushrooms.

HOW TO OBSERVE #NationalLinguineDay

If you enjoy pasta but haven’t cooked with linguine, give it a try. Try new sauces and fresh ingredients. Share recipes or test out new ones. No matter your preference, lightly seasoned, spice, or taste of the ocean, linguine will satisfy your craving.

Invite some friends over and open a bottle of wine. Break open the pasta and get cooking!

Enjoy these delicious linguine recipes and use #NationalLinguineDay to post on social media.

Linguine with Clam Sauce
Chicken and Onions Over Linguine
Mushroom Linguine


National Day Calendar did not uncover the origins of this delicious food holiday.



On September 15th, National Cheese Toast Day savors the cheesy goodness of this classic dish.

Simple but delicious, cheese and toast go well together. A little butter helps everything meld together nicely, too. The crustier the bread, the better. It makes an excellent side dish, but cheese toast also serves up a satisfying snack. 

While food holidays aren’t in short order on the calendar, we can’t surpass them because of the carb count. Cheese and toast perfectly combine to dunk into soup. In the middle of dinner conversation, a chunk of cheese toast waved in the air emphatically punctuates your story, especially when finishing a monologue with a satisfying bite. 

It might surprise many to know the treat was created by Del Johnson. In 1958, he opened his first Sizzler restaurant. It was an instant success. And although the recipe changed a bit over the years, the concept of Cheese Toast hasn’t.

Over 60 years later, Cheese Toast continues to be a favorite dish across the country. With the best cheeses and bread, served up as an appetizer, with soup or with the main course, cheese toast pairs well with many dishes. 

HOW TO OBSERVE #CheeseToastDay

Whether snacking or craving comfort food, cheese toast fits the bill. Order up some Cheese Toast for lunch or dinner. If you don’t have a Sizzler near you, try your hand at making Cheese Toast at home. Share photos or your recipes using #CheeseToastDay on social media.


Sizzler USA founded National Cheese Toast Day in 2015 to celebrate this flavorful combination.

The Registrar at National Day Calendar declared the day to be celebrated on September 15th annually.

National Neonatal Nurses Day - September 15


On September 15th each year, National Neonatal Nurses Day recognizes those who care for the most fragile patients as they take their first breaths. The celebration takes place in the middle of National Neonatal Intensive Care Awareness Month. 

Neonatal nurse specialists work with newborn infants who are delicate at birth due to a variety of reasons. They may have been born premature or born with birth defects, infection, surgical issues, or heart problems. Neonatal nurses also provide care for healthy newborn infants immediately following their birth.

The demand for neonatal nurses continues to rise. Their expertise and training meet the needs of the youngest, most fragile, and critical patients in any hospital. Many require 24-hour care and attention. While most neonatal newborns spend a month or two in the hospital, some require longer care. The neonatal nurse provides their care for the duration of the stay. Some neonatal nurses provide care beyond the neonatal period. 

The day celebrates their dedication and commitment to the profession. It also is a way to encourage others interested in the field to take a closer look. With the growing demand for qualified neonatal nurses, the more students stepping up to the challenge of this satisfying career, the better. 

HOW TO OBSERVE #NeonatalNursesDay

Thank a neonatal nurse you know by sending them a card. Let them know how much you appreciate the work they do. Hospitals and other professionals will take the time to celebrate their neonatal nurses and encourage them every day. If you’re a neonatal nurse, plan to attend a job fair to share your experiences with others considering the profession. Use #NeonatalNursesDay to share on social media. 


The National Association of Neonatal Nurses established National Neonatal Nurses Day in 2000 to showcase the work these specialists do every day. The day honors neonatal nurses across the Nation for the care and protection they give to save the precious lives of babies. 



On September 15th, tip your hat for National Felt Hat Day! The observance recognizes a stylish head protection worn throughout history.

Historically, men and women wore hats as protection and status symbols, too. This time of year, people traded in the lighter, cooler straw hat for the warmer felt hat. Additionally, etiquette dictated what hats men and women wore and where. For example, good behavior required men (mostly) to learn to don and doff the hat at an early age.

While primarily made from wool, felt can also be made from the fur of other animals. Usually, rabbit and beaver were the furs of choice. During the 16th and 17th centuries, beaver hats reached popularity but over trapping depleted the population.

The phrase “a mad as a hatter” comes from the use of mercury nitrate in haberdasheries in the late 18th and early 19th centuries. Over time, daily exposure to this metal caused these tradesmen to develop dementia, tics and other symptoms. These unusual side effects caused people to believe their hatters had gone mad.

Over the centuries, many styles of felt hats have made their debut. We can identify an era by many of them. Its buckle will quickly identify the Quaker, and the stovepipe reminds most Americans of one of its most beloved presidents. Others have odd names such as pork pie, bowler, and stingy brim.

HOW TO OBSERVE #NationalFeltHatDay

Celebrate by donning your favorite felt hat and snapping a picture. Try out styles you’ve never worn before. Go on a hat shopping expedition. Study up on millinery techniques.  You might just find out the Fanchon, flower pot, Reubens, Fedora, or a Panama is really your style instead. Use #NationalFeltHatDay to post on social media.


National Day Calendar’s research continues to try to unearth the source for National Felt Hat Day.



National Crème de Menthe Day on September 15th recognizes the creamy peppermint-flavored liqueur used in cocktails and desserts. Enjoy your favorite combination to celebrate!

Many of the liqueurs we enjoy today started as tonics and cure-alls. And we thank pharmacists for bringing them into existence. Crème de menthe (mint cream) is one of those liqueurs. French pharmacist, Emile Giffard, studied the cooling and digestive properties of mint. His research led him to a recipe for crème de menthe.

Crème de menthe is sweet and mint leaves (usually Corsican mint) give crème de menthe its green color. However, when extracted, the liqueur is colorless. This form of the liqueur is called white crème de menthe. Unless color is essential, both varieties have similar flavors and are interchangeable in recipes.

The traditional formula involves steeping dried peppermint or Corsican mint leaves in grain alcohol for several weeks. This method creates a natural green color.  The following steps include filtration and the addition of sugar.

Several cocktails include crème de menthe as an ingredient. Two popular cocktails include Grasshopper and Stinger. Because of mint’s digestive qualities, crème de menthe makes an excellent after-dinner drink.  Also popular in the kitchen, it is used in many recipes as a flavoring. To make a chilly adult milkshake mix crème de menthe with ice cream.  Add chopped pecans or shaved chocolate as a garnish.

HOW TO OBSERVE #CremeDeMentheDay

Try crème de menthe for the first time or the hundredth. Add it to a dessert or mix up a cocktail. Stir in some chocolate for a mint chocolate flair. Encourage your favorite restaurant or dessert shop to celebrate the day, too. Give them a shout-out for their amazing creations, too. If you don’t have a recipe to try at home, check these out:

Creme de Menthe Squares
Grasshopper Pudding

Share your crème de menthe recipes. Use #CremeDeMentheDay to post on social media.


While National Day Calendar continues seeking the origins of this dessert holiday, we’ll be sure to update you when we do.

September 15th Celebrated (And Not So Celebrated) History


After being an itinerant preacher for several years, Antoinette Blackwell is ordained as the minister of the Congregational Church of South Butler in New York. Upon her induction, she became the first woman ordained in a recognized denomination in the United States.


Chemist, Constantin Fahlberg, receives a U.S. patent for a sweetener he accidentally discovered. U.S. Patent No. 326, 281 describes the process for making saccharine. The artificial sweetener would revolutionize the dieting world and at turns create chaos in the food industry.


Sterling P. Fergusson launches the first gas weather balloon in the United States. Made of rubber and measuring 6 feet in diameter, the balloon was filled with hydrogen and ascended from the grounds of St. Louis Louisiana Purchase Exposition. The meteorologist, working for the Blue Hill Observatory out of Milton, MA, included instruments for measuring atmospheric conditions at high altitude. The basket also included information for returning the basket once it descended back to Earth.


While conducting experiments on a strain of influenza, Alexander Fleming discovers penicillin. The revolutionary medication served to control bacterial infections and saved millions of lives.


Tapping into the space-exploring imaginations of a generation, the television show Lost in Space premieres.


Are you hangry? Research at the University of Cambridge shows the fluctuations of serotonin levels in the brain when someone hasn’t eaten or is stress impact areas of the brain that control anger.


Salud! Fernando Ortiz Torres breaks world record for the largest wine-tasting. The Plaza de Toros in Aranda de Duero, Spain hosted 5,095 wine tasters in the single-day event.

Recipe of the Day

Apple Butter Meatball Subs Recipe

Prep: 10 minutes
Cook: 4 hours
Total Prep: 4 hours 10 minutes
Servings: 6

These tangy apple butter meatball subs will hit the spot for summer cookouts or midweek meals. Make them ahead and celebrate all those special days!


1 cup apple butter
1 cup BBQ sauce
16 ounces of frozen meatballs
6 hoagie rolls
12-18 slices of provolone cheese
1/4 cup chopped green onions



Mix apple butter (we used a homemade spicey apple butter) and BBQ sauce together. Add meatballs to crockpot and pour the sauce over top, coating all the meatballs well. Slow cook on high for 4 hours.

Lightly butter and toast the hoagie rolls. Divide the meatballs evenly between the rolls. Top with cheese. Garnish with green onions.

Recipe credit:

Michele S. – National Day Calendar

September 15th Celebrated (And Not So Celebrated) Birthdays

James Fenimore Cooper – 1789

The American writer is best known for his frontier stories. In his Leatherstocking Tales, he created memorable characters such as Natty Bumbo and Hawkeye.

George Franklin Grant – 1846

Not only was Grant the first African American on the Harvard faculty, but he also invented the first golf tee. While he never marketed the invention, it was patented on December 12, 1899.

Jan Ernst Matzeliger – 1852

Matzeliger’s invention demonstrated how innovation often leads to more jobs, not fewer. In 1883, the shoemaker received patent No. 274,207 for a lasting machine that could produce 700 shoes a day. Before his invention, production was slow, and shoes were mostly handmade. However, after his machine was put to use, more employees were required to keep pace with the increased production. 

Edward A. Bouchet – 1852

The physicist and teacher became the first African American to earn a Ph.D. in America. He would advocate for better educational opportunities for his students and was a member of the Franklin Institute and the American Academy of Political and Social Science.

William Howard Taft – 1857

The 27th president of the United States was more than a politician. After serving his presidential term, Taft continued his distinguished law career and became the 10th chief justice of the United States. In 1911, during his presidential term, he also proposed an idea that became known as the Chamber of Commerce.

Claude McKay – 1889

A student of the Tuskegee Institute and Kansas State College, McKay’s poems and novels spoke of social and political divisions. At the time, his work was a major influence in the Harlem Renaissance. Works like his novel Home to Harlem and poets like If “We Must Die” brought a literary response to the movement.

Agatha Christie – 1890

The prolific mystery writer is also the world’s best-selling author of fiction. With estimates soaring to the 2 billion mark, Christie’s works have also inspired television series and movies.

Sir Donald Coleman Bailey – 1901

The British civil engineer is known for developing a type of pre-fabricated, portable truss bridge for military maneuvers. During World War II, the British, Canadian and US military used the bridge extensively.

Fawn M Brodie – 1915 

The biographer best-known for her book Thomas Jefferson: An Intimate History was also one of the first female professors of history at UCLA.

Jessye Norman – 1945

The Grammy-winning soprano earned a reputation for her broad range and dramatic performances.

Tommy Lee Jones – 1946

In his more than 30 year career, the award-winning actor has played such memorable roles as Agent K in Men in Black, Samuel Gerard in The Fugitive and Woodrow F. Call in the television mini-series Lonesome Dove.

Prince Harry – 1984

The Duke of Sussex is the second son of Charles, Prince of Wales and Diana, Princess of Wales.

About National Day Calendar

National Day Calendar® is the authoritative source for fun, unusual and unique National Days! Since our humble beginnings on National Popcorn Day in 2013, we now track nearly 1,500 National Days, National Weeks and National Months. In addition, our research team continues to uncover the origins of existing National Days as well as discover new, exciting days for everyone to celebrate.

There’s a celebration for everyone. While National Road Trip Day satisfies the itch to wander, many pet days let us share our love of animals. National 3-D Day and National Astronaut Day honor the advancement of technology, too. Every food day you can imagine (National Avocado Day, for example), will keep you celebrating, also!

Be sure to stay in the know by signing up for our e-mail updates. Also, follow us on Facebook, Twitter, and Instagram

Our Ambassador Program is another way #CelebrateEveryDay®! Whether you become an ambassador or follow one of the savvy ambassadors, their fun videos and posts will keep you prepared for every holiday.