-Sticks. I cannot stress enough the importance and status of having a good stick. It is a symbol of power. "He who hath the stick, hath the power." The bigger the stick the greater the power. Basic pirate style sword fighting with sticks has been replaced first, with Star Wars lightsaber fighting and more recently with Naruto (anime) style fighting.
Sticks are also essential for poking and turning over dead stuff, and poking and flinging dog poo at your enemies.
-Kids that eat gross stuff. Mainly worms. At our school it is an angelic looking six year old girl. Other kids are excited and yet repelled by this, but of course are always there to encourage it. Once a worm has been devoured, it is an unspoken rule that you must keep a distance of at least three feet in case of wormy upchuck or just being touched by wormy fingers.
-Biters. Most of the time they seem normal, until they freak out and become pitbulls. Cute pitbulls but just as tenatious. Every child knows who the biters are, what sets them off, and gives them a wide berth, keeping limbs away from the mouthal area. Except for the new kids, they usually find out the hard way.
-Firestarters are pretty much at the pinnacle of kids the grade school bad boy scale. They often lure easily duped kids behind the bushes to watch them burn something. It could be anything, and probably it belongs to someone else. Often they are discovered, sometimes because of a telltale waft of smoke, but more likely because other kids really love to snitch about something that is considered quite bad in the world of elementary school no nos.