innocent

I work with children every day all day. people say children are the innocent, the younger they are the more innocent they are. it's true they are innocent, but to what? the kids I work with are 4-6 and there is a fair share of crying each day because someone isn't sharing, they tripped and fell, someone pushed them, the list goes on. by this age they know everything isn't always fair, they know scrapped knees heal and they know that some people are nicer than others. if they already know the flaws in out world than how are they innocent? sure these are minor reflections of our society's problems but to a child little problems have the same impact as our big problems. so I ask again why do we view children as innocent?