pretty cool, says university of chicago mathematician amy wilkinson. >> what we would call fundamental constant. it comes up in everything you do in mathematics. >> you can't get away from pi. >> you cannot escape pi. pi is always there. >> reporter: the massachusetts institute of technology put out this video, telling applicants they could log in on pi day 3/14/15 at 9:26 to see if they were accepted. kids at new york's museum of mathematics count down to the moment of pi. of course, here in chicago, what would pi day be without deep dish? at my pi pizza, a slice and a drink today will cost you $3.14, of course. and our facebook friends are sending out all kinds of pi filler to show how they're celebrating. >> pi deserves a day. >> especially if it's pumpkin. >> reporter: so do the math, and have a slice. 3/14/15 won't come around again for another 100 years. kevin tibbles, nbc news, chicago. >>> when we come back, a swim team making waves in more ways than one. >>> we end tonight with a story of a swim team. there are a lot of those, but this one isn't made up of elite athletes, and