I find that the part of the beauty of the film and its message about diversity is that it comes directly from the point of view of the indigenous population. From my American grown perspective, I can see the goal or worth in what the British colonists in Australia are trying to do. While they are trying to teach developed skills and knowledge to the children of the aboriginals, they are still misguided and wrong in doing so. This is where the unique POV comes into play: the children make decisions and are shown doing things that directly go against what we know from our perspective.
The kids pursue the thing that will make them happy: to live with their family in the way they were raised. They reject colonization, they reject the development of their people. They don't care about what they are lacking or what they could gain, they only care about the bonds that have been taken from them--and justly so. It's an interesting look at what colonization looks, feels, and does to the people that are at the other end of it. I have only interacted with a handful of works that offer up this same kind of perspective, and it's rare that they are intended for children audiences. Whale Rider and Rabbit-Proof Fence both work at this in a very graceful and sophisticated way that allows children to interact with tougher ideologies.
I'm sure the concern exists there for the well-being of the children in the movie--and because of this, the child watching the film must ask the hard question as to why. Why would they risk so much to get home? What is the problem at hand with the colonization? Is it the intent? Is it the obvious racism? Is it because the government actually wants to help or are they just trying to impose their own cultures and standards on people without taking into consideration how they feel about it? A film like this forces a kid to think about things they wouldn't otherwise think of or have to deal with, and I think that's really important in good children's media. I believe this would be a good immersion for a child into the world of 4th cinema, and allow them to see that there are different perspectives to problems and to history and that there is more to consider than just the immediate geography and culture outside their house.