A 3rd grade class was visiting a sheep ranch, and in due order made their way to the shearing shed. Their guide, a good-natured hand called Otter, said, "And now you're gonna see Ol' Rex the sheep get AAALLL his wool cut off, followed by his lovely ewe, Vanessa!"
Farmer Dan walks in leading two sheep. Otter takes Rex's lead and gets to work. As soon as the clippers start, Farmer Dan begins rubbing his crotch and moaning. The longer Otter works, the more excited Farmer Dan gets. Then as soon as Otter finishes with Rex, Farmer Dan drops his pants and is soon balls deep in Vanessa.
The schoolkids start screaming and yelling, and their teacher throws herself between them and the scenario of Farmer Dan and a very surprised Vanessa. Otto smiles knowingly at the teacher and says, "I'm sorry ma'am, I should have warned you: Ol' Farmer Dan just *loves* cuckin' the shorn!"