This is a really great website that looks at representations of First Nations. It looks at a variety of political and pop culture representations with thoughtful critiques. For example there is an article about the new addition to the Harry Potter world as it is set in the US where the author sets out her concerns about how the indigenous population might be represented.
It is a very interesting website to read, but I think it could be a good resource for the classroom as well because it deals with some pop culture representations.
This is a collection of links from the Ontario Institute for Studies in Education at the University of Toronto that deals with the representation of First Nations in the media.