Just want to chime in that I completely agree with Kai. My DD10 tested at an 8th grade+ level in 2nd grade. There were very few books that seemed appropriate content-wise that were at her level. She is imaginational and emotional OE so I limited what she got her hands on. The first Harry Potter gave her nightmares for a week when she was in 1st/2nd grade (can't recall exactly). What she reads right now is pretty standard 4th-6th grade reading. She just reads a lot of it very quickly.