My Junior year we were in the gym for P.E class when out of no where all the doors started shaking and rattling like crazy. The basketball hoops were in the up out of the way position in their pulleys bouncing up and down. There was a group of us kids, probably 20 or so, and every last one of us was the thinking holy fuking [Bleeeeep!]! It's ghosts!! Everyone. What the hell else would it be? Then about 10-20 seconds in we here a woman's screaching out "EARTHQUAKE!!!" It was our uber badass teacher/ wrestling coach/ Olympic alternate. Lol. I'll never forget that day. We couldn't feel the floor/ ground moving and with the layout of a gym there are only so many moving parts to see visually move. Funny, funny chit.