This is great! I like how you're showing Emily's struggles with her powers, and her anticipation of some of the problems she'll likely have based on her brother's experience.
And I, too, like Nathan. You've done a good job of portraying him as a kid with a reputation as a trouble-maker, but one who seems reluctantly fascinated by Emily. He seems to have a history at the school - doesn't seem to be another 'new kid.' I'm hoping that rules out his being a threat to Emily and/or Jack re Lois and Clark's investigation.
Perhaps he'll actually turn out to be an ally? He seems to be around watching a lot, but based on Emily's changing perceptions of him, it sounds like there may be some hope of them becoming friends, of a sort. Maybe if danger looms he'll be on her side.
More soon?
This is very good.
~Toc