At the website KOMPLEXIFY! a mathematician named Travis celebrates his love of mathematics in various ways, including humor and verse. He supplies lots of limericks and parodies, including Tom Lehrer's parody of "That's Entertainment" entitled "That's Mathematics" which I offer below. (Here is a link to the rich list of Travis' poetic postings.)
That’s mathematics! by Tom Lehrer
Counting sheep
When you’re trying to sleep,
Being fair
When there’s something to share,
Being neat
When you’re folding a sheet,
That’s mathematics!
When a ball
Bounces off of a wall,
When you cook
From a recipe book,
When you know
How much money you owe,
That’s mathematics!