Summer is a-Comin' In

“Sumer Is Icumen In” is the oldest English song in existence, written down in the mid-13th century in Middle English:

Sumer is icumen in, Loude sing cuckou!
Groweth seed and bloweth meed, And springth the wode now.

I have updated the words a bit. Have your students play this as a round! Any number of performers can play on the same piano in different octaves.