"Smack Cam" is when people (typically douchey bros or bitchy mean girls) smack unsuspecting victims and then post their stinging faces and shocked screams on Vine.
According to his Vine profile, Aaron VanDeventer is an 18-year-old senior from Grand Ledge, Michigan who enjoys track and thinks it's hilarious to slap little girls in the face until they cry. A video he posted of two assholes harassing a tearful girl has been been retweeted 625 times and counting on @VineLoop, "The Official account for the YouTube channel FunnyVines!"
Vines of boys hitting girls are instant #SmackCam hits; here's a video of a guy violently slamming a girl on the head with heavy jug. She appears to be so stunned that she falls over.
You don't need to wonder what your 8th grade sleepover parties would've been like if the grade's Queen Bee had Vine; just check out these two videos. This school bus #SmackCam is like something out of a warped John Hughes movie.
Sure, some of the 1,000+ #SmackCam tweets are probably all in good fun — the inaugural #SmackCam was a joke between friends — but the ones I've seen remind me of Emily Bazelon's definition of bullying: "physical or verbal abuse, repeated over time, and involving a power imbalance. In other words, it's about one person with more social status lording it over another person, over and over again, to make him miserable."
Update: The girl who got smacked in the head with a jug was apparently in on the joke. Violence against women is hilarious!!