Children demonstrate bully behaviors for various reasons. Some do so because becuase they are trying to make themselves appear to be better than they actually are. This can be done just by laughing at someone else or saying something negative about someone. Instantly they portray themselves as "better than that." You have met some of the one-uppers type or the laugh at anyone type. Keeping the other people as less than them makes them feel superior, for the moment. In my experience, this is more of a self-esteem issue with them. Getting them to feel that others will like them as they are, is the key to making this less of a problem. Laughing at others fuel others to do the same. Instead, teach them to comfort others instead of poking fun at them. It will not only make them look better, but also make them feel better as well. Imagine if everyone felt secure in who they were, how wonderful and peaceful life could be.....