On March 14, mathematicians and much of the world celebrate Pi Day. Since the approximation of the number pi is 3.14, March 14th was picked for the day. It was first celebrated in 1988 in San Francisco. As a math teacher I get excited for Pi Day, however our school is always on spring break on March 14th so I don't get to celebrate it with my students. This year I thought I would do a round-up of Pi Day activities and try to share ones for different age groups since much of what I see are for younger kids and I teach high school. Be sure to start your celebration with some pi jokes and riddles like these. Some of the Best Things in Life Are Mistakes shares a round-up of free Pi Day decorations! By the way Pi Day is also Albert Einstein's birthday. You can also have a birthday celebration for Albert!