On Square Root Day, the day and the month are both the square root of the last two digits in the current year. (For example, today's date is 3/3/09; 3 is the square root of 9).
According to Wikipedia, a Redwood City, California high school teacher named Ron Gordon first created the day for 9/9/81. Square Root Days occur nine times each century. The last day was five years ago, Feb. 2, 2004; the next is seven years from now, on April 4, 2016.
To celebrate Square Root Day, you could:
- Eat a square meal
- Drink root beer out of square-shaped mugs
- Tie square knots
- Cut root vegetables into cubes (a square on all sides)
- Go square dancing