I know that a child's head banging can be a scary situation for a parent. We don't want to see our children hurt. However, generally, children don't hurt themselves by doing this. It is a strategy that children use to express their frustrations and/or to get attention from a parent(s). To give you a bit more informatioin, I've attached a couple of web cites that I hope you will find helpful. If not, consider contacting your child's pediatrician or consulting a child psychologist.