A little arty, a little abstract, a little sad. I'm not sure to whom I would recommend this odd, brief little story of loneliness -- certainly not to children, it would be depressing and potentially upsetting.
I don't think everything distressing is necessarily inappropriate for children, but there are plenty of important real topics they should know about without inflicting this strange, artificial tale of a girl trapped alone in a model castle in a museum case upon them. When I was little it would have given me nightmares and probably caused heebie-jeebies about visiting the museum. The art was sort of interesting but I didn't get at all what the author wanted to do here.