The focuses in the image are the children sitting around chatting with one another and the place where they are sitting at. They take up most of the image thus they should be the focus of it.
The setting is a slum in a poor country where the characters probably live and the characters are the children who are sitting and chatting, the main focus.
I think that the story behind this is the children are living in slums as they are very poor and regularly go hungry because they look so thin. They could be working at their age and this moment could be one of the few times they have to rest and chat.They may seem to be happy now but this could just be a shadow of their daily lives.
The message the photographer wants to convey is that we must do something to help these poor children get regular meals, proper medical care, better housing, education and better lives. They should get an education to help them succeed better in life when they grow older.
I like the fact that these children were photographed at the time when they were chatting happily and if I were the photographer I would take the photo from a point in which it just shows their laughing faces and not where they are sitting so as to show these children in a better light.