Number two, I knew I would get to the bottom of your devious secrets sooner or later. Seriously, this is why we use #2 pencils on tests. This has been bugging me for years.

Cool side note, if you run some chapstick over the answer reader, it is rumored the scantron cannot process the answers and lists them all as correct. A nice little hack for all you kids out there who want to fake it until you maybe never make it.

[Vid Via SciShow]

Tags: #2 pencils, geek, graphite, hack, How-to, nerd, Science, tests