The middle 50% of typical non-gifted second graders are reading at Lexile levels between 150L and 500L.

http://www.lexile.com/about-lexile/grade-equivalent/grade-equivalent-chart/

Henry and Mudge, the Star Wars books, the Animorphs books, and Ricky Ricotta's Giant Robot are around the top end of that range.

ETA: The Lightning Thief is Lexile level 740L, around the middle of the average Lexile range for sixth graders.

Last edited by aculady; 10/28/11 09:33 AM. Reason: Added more info