Status: Urban Legend
Here's an odd urban legend that I just stumbled across. Supposedly if you smear chapstick down the side of a scantron sheet (the kind used for standardized tests such as the SAT), the grading machine will mark all your answers correct. The theory is that the chapstick will interfere with the scanning light, confusing it into thinking that your answers are correct. Needless to say, this doesn't work.
Some guy named Richard Mangahas has written a short article
detailing all kinds of theories about ways to cheat on scantron tests, including: marking or deleting the black lines along the side of the page, filling in the bubbles with cross-hatches, or placing tape along the side of the page. I don't think any of these methods would work either. (Though Mangahas claims some of them work 25-30% of the time... which is about the same percentage you would expect from guessing at the right answer.)
Maybe it was kids armed with chapstick that caused all those SAT-test score errors recently.