Perhaps the Innu and the Inuit feel that the term First Nations doesn't quite work for them?
Well they are considered to be a part of the "first ones here club" I think it probably has more to do with politics. If I'm remembering correctly, there's a... *waves hands* Assembly of the First Nations (I totally had to google the name of that), and it's the Assembly that represents the groups as a whole to the government (although individual bands will too) and maybe the Inuit and Innu feel that they weren't being represented as they choose, so aren't apart of the Assembly of First Nations, so don't fall under the heading. But I'm going off of suppositions and shaky memories here, so I could be totally wrong.

It seems really high. I know that 25% of my high school cohort certainly didn't drop out, but I'm sure these things vary from place-to-place and in different time periods.
Yeah, it must be a Toronto statistic, because I know 25% of my high school didn't drop out either.
Although, I know the community where my best friend grew up had a ton of drop outs, so maybe it's a provincial average. *shrugs*