SquareZ
Dance until the earth dance.
--Hilda Doolittle
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.