If you have young-ish kids in school, they may have learned a song called "Do Your Ears Hang Low?" in music class.
From the Wikipedia page: "Do Your Ears Hang Low?" is a children's song that is often sung in schools, at camps and at birthday parties. Here'a a link to a youtube version
I was always puzzled by one particular lyric: "Can you throw them over your shoulder, like a continental soldier?" ... and so I ended up looking up the song on wikipedia to learn the origin of that particular lyric (it is a very puzzling lyric if you think about it, and suggests a military origin. I thought "That sounds like someone from the navy shit-talking someone from the army").
I found the following gem: "A common belief is that the lyrics refer to the long ears of a hound. It appears considerably more likely, however, that the song originated as the obscene "Do Your Balls Hang Low?", and was later sanitized."
Which makes me wonder if whoever assigned this song to elementary school children understood it's origins.
(It seems reaonable to assume they do not)
The root origin of the song is very troubling: "The origin of the song is most likely George Washington Dixon's "Zip Coon", a racist ditty penned in 1838 and later adapted to the less offensive "Turkey in the Straw". Variant versions with obscene lyrics include "Do Your Balls Hang Low?" and "Do Your Boobs Hang Low?"
The earliest apparent report of "Do Your Balls Hang Low?" is said to date from about 1900. Certainly the song is known to have been sung by British soldiers on the Western Front during the First World War. Lyn MacDonald reports that, on one occasion in 1916, General Douglas Haig heard it being sung by a column of soldiers as they marched past on their way to the Somme.
 
For completeness, I'd like to include the original lyrics in their glorious entirety:
Do your balls hang low?
Do they dangle to and fro?
Can you tie them in a knot?
Can you tie them in a bow?
Do they itch when it's hot?
Do you rest them in a pot?
Do you get them in a tangle?
Do you catch them in a mangle?
Do they swing in stormy weather?
Do they tickle with a feather?
Do they rattle when you walk?
Do they jingle when you talk?
Can you sling them on your shoulder
Like a lousy fucking soldier?
Do your balls hang low?