(...in AP Bio class for example)
Teacher: "And so the mitochondria...blah blah blah etc"
Confused student: (smashes face on desk) "Ahhh what is this bullfuckery. It makes no sense >.<"

or something such as...

(rainbow unicorn flies across the sky and eats rainbows and poops butterflies and brings you cookies)
Person: wow...bullfuckery...wtf just happened...win...

or perhaps...
Student A: "oh crap, i forgot to do my homework"
Student B: "way to go"
Student A: "yeah...ill just write down some bullfuckery"

Yo dude, Darryl is turning 40 next year. That's what I call geriatrocity.

That teacher is absolute bullfuckery