A phrase you yell in class when you have no idea what the teacher is talking about, and you have no idea what the hell is on the board. It's softer that son of a bitch, yet very effective. The teacher will automatically catch that you have no clue and stop to help you.
Teacher: 3xy + dy/dx 75497h54utrw98yht4itr;ogeo;iugfe vdkuvdsogusvou
Student: *???* SON OF A HOOKER!
Teacher: Oh gee, I'm sorry, let me help you understand this bull crap I've got here on the board!
Student: Thank you!