The first truly original joke I remember making was in 9th grade Latin class. Our textbook included a photo of a statue of the Capitoline Wolf (the kindly beast who adopted Romulus and Remus).
I took off from the 1950s’ surrealistic ads for Maidenform Bras.
My joke – which I still think is funny, as did my classmates – was a mock ad:
“I Dreamed I Was the Capitoline Wolf in My Maidenform.”
(I left off the word “bra” in deference to its being a 9th grade Latin class in Massachusetts.)