This improv game is in the following improv game categories:
4 players sing a song about a subject, given by the audience, on an Irish-souding tune, one line at a time.
4 lines makes 1 verse; after the frist verse, a second verse is started by player number 2; and so forth. After
4 verses every player has both started and ended a verse and the song is over.
Played quite often in Who`se Line is it Anyway. You`ll find plenty of examples on YouTube.com.
Invent your own choreography and have the players dance as they sing.
See also Do Ron Ron for a similar structure.