SquareZ
Man needs nothing so much as the dance.. a man who does not dance is good for nothing...All human unhappiness, all blows of fortunes, which history reports to us, all mistakes of politics, all defeats of the great commanders result solely from the fact that the dance is not understood.
--G.H. Chesterton
Calling Ideas for May 19, 2012

This is:

Frog Jumping Jubilee Day
In 1928, the first jumping frog contest was held in Calaveras County, California. See my original comments here.

You can break out your frog songs: "Joy to the World" ("Jeremiah was a bullfrog") and "Froggy Went a Courtin'". You could even change the words to "froggy went a jumpin'". Dancers probably wouldn't appreciate frog legs as a snack, however.