A FEW YEARS AGO my daughters and I were searching for sand crabs on a white-sand beach near Monterey. A group of sixth graders descended on us, clad in the blue trousers and pressed white shirts of their parochial school. Once lost in the sounds of the surf, away from their teacher’s gaze, they called one another by nicknames and mocked the way one laughed, another walked. Noogies and rib pokes, headlocks and bear hugs caught the unsuspecting off guard. Two boys dangled a girl over the waves. Three girls tugged a boy’s sagging pants down. Dog piles broke out. In a surprise attack, one girl nearly dropped a dead crab down a boy’s pants.

the anatomy of teasing by a professor of psychology at the University of California, Berkeley.