A teacher has his class fill their pockets with iron filings and stand while he explains the concept of electromagnetism to his students... ""If we see the difference between a milliwatt and deciwatt, you'll notice that the iron I had you put in your pockets is pulling down, what does this prove to us, class?"" A little girl raised her hand and said, ""That we get heavier?"" The teacher looked at her, rubbed his eyes and said, ""No, but you're pretty so you've got that going for you... anyone el…