During the course of my research in middle-school playgrounds over the past seven years, I observed the following two episodes of behaviour. In the first, an 11-year-old boy chased another across the playground at full speed before he caught up with him and grabbed him round the neck. The first boy manoeuvred the second boy into a bear hug, which, with the struggling of the second boy, ended up as a head lock. The boy who was restraining the other delivered a number of punches to the face of his opponent, who broke free some thirty seconds later and made good his escape by running away at full speed. In the second episode, two other 11-year-old boys stood facing each other. The smaller of the two boys poked the other with his index finger lightly, but repeatedly for some twenty seconds. The other boy used his hand to try to deflect these pokes. While he did not appear to be unduly upset by being on the receiving end of them, he did show signs that he would have liked to move away from the other boy.