I applaud you for being such an advocate and a teacher (I know how demanding that it without having "special" cases). I agree with delbows about making sure he's not accelerated too much to be reading inappropriate things for a 7 year old. Even though my kids can read at higher levels, they mix it up--all different levels, all different topics, fiction, non-fiction, biography, etc. I think the goal is to develop a passion for reading now and not worry so much about level. If he's bored, clearly he needs to step it up a couple knotches.
My 8 yr old went through a period where he didn't read much because even though he could read advanced books, he needed the satisfaction of finishing shorter books (the trick was to find good, advanced books that were about 100-200 pages long). He also used to have nightmares when he read scary material and would get very emotional about things like global warming. I guess the more mature books will require some one-on-one discussion and keeping his parents informed of what he's reading, so maybe they can talk about things, too. This year he has become an avid reader of bigger books. Keyboarding (and occasionally dictation) have both helped him because his fine motor/handwriting skills are behind.
My oldest son's IEP has a goal about reading 5 books and having personal discussions with the teacher about them. Throughout the year, the teacher will point out books to him that expand on a topic they're covering in history, he'll read, they talk. He doesn't have to read all that she recommends, but just the ones that interest him. So far it's great.
