April 12th Is liquorice day. !Note - liquorice (BrE) / licorice (AmE)
4 / 4 / 16Square Root Day - The 4th day of the 4th month of the 16th year. 42=16 4x4 = 16 The next square root day won't be until 2025. Can you work out what date it will fall on?
March 31st Today is World Backup Day. So, get backing up. http://www.worldbackupday.com/en/
23rd March Is OK day to mark the date that the initials “O.K.” were first published in The Boston Morning Post. Okay? It's also National Puppy Day, so everything must be okay.
March 22nd Today is World Mime Day. Set up to coincide with the date of birth of a legendary French mime artist Marcel Marceau (March 22nd 1923 - September 22nd 2007). http://www.worldmime.org/