If they are "watching," then why didnt theTailies know about Ana Lucia and Libby? Maybe watching all over the island was not what they meant only on the other island watching the cages. Or maybe they just didnt tell the children

I think they were there to watch something specific. Like Juliet's trial, or more likely, Juliet's execution.

Many dictatorships demand that the local population watch executions. It is a common method of population control by fear.

I don't think Cindy or the children knew what happened to Ana Lucia after she got to the beach camp.

I don't know about cindy, but I don't think the children know about Ana Lucia. It seemed like Cindy was sticking up for the others, I believe she said something like "it's not like that" when Jack asked her about being there. Sorry I don't know the exact dialogue but I remember the impression I got from it. Like cindy maybe didn't mind to much being there. I don't know if she knows about Ana Lucia or not, but she might.

Ben has a lot of (indirect) blood on his hands, now what I think of it: Libby, Ana, Pickett, the other that was shot following "the list"... Ethan, Goodwin, the others that Eko killed on the beach... the headcount is rising.

how could they know about what s been going on at the crash site?we dont even know what theyre there for ,yet.its obvious that theyre part of some kind of project-experiment themselves...forced to watch people in captivity and the likes...psychological experiment.its natural,they dont know much