A Maths Class Exam

"How easy this maths exam will be, How simple the maths to be done?" You understood exactly what the teacher had taught, Had taught before the test had begun. On the board it was: ten plus two is… And then, what’s ten minus four. On the board it was easy to see how it was solved, But that was prior, preceding, before Seeing the test needing a million computations, Written in some bizarre scripted form, The test asking to figure something like: Calculate the mass of last nights thunderstorm. Then: “What? Huh? Oh man, I’m in trouble, Does it matter if every answer is guessed?” The “I had no idea of any of that”, Finishes with, "That was an easy maths test?”