May 21

American Red Cross Founder’s Day,End of the World or Rapture Party Day, I Need A Patch For That Day, National Endangered Species Day, National Wait Staff Day, Sister Maria Hummel Day, Victoria Day, World Day for Cultural Diversity for Dialogue & Development, National Strawberries and Cream Day

May 20

Eliza Doolittle Day, Weights & Measures Day

May 19

Boys Club Day, May Ray Day, Mike, The Headless Chicken Day, National Asian & Pacific Islander HIV/AIDS Awareness Day, Neighbor Day, Pentecost, World Autoimmune Arthritis Day, National Devil’s Food Cake Day, World Baking Day, National Quiche Lorraine Day, Pick Strawberries Day

May 18

Armed Forces Day, HIV Vaccine Awareness Day, I Love Reeses Day, International Museum Day, Mother Whistler Day, National Learn To Swim Day, O. Henry Pun-off Day, Visit Your Relatives Day, National Cheese Soufflé Day

May 17

Endangered Species Day, International Virtual Assistants Day, NASCAR Day, National Bike to Work Day, National Defense Transportation Day, National Pizza Party Day, Syttende Mai, World Hypertension Day,  Information Society Day, World Telecommunications Day, World Neurofibromatosis Day (NF Day), National Cherry Cobbler Day