Green Eggs and Ham

[HIU8]

I'm trying to get a bearing on DS's reading level. His school does not do levels (does not follow the county/state at all). I know some of his K work my friends DS is doing in 1st and some he did in K. My DS is doing 1st grade math (they put him in a higher class for math--he is where other 1st graders at his school are level wise). I researched and it seems that DS is well above in reading as well. FWIW, the teachers had talked about moving DS to 1st back in November and then decided not to. We meet again in a few weeks and I want to go in armed with a better idea of where my DS is academically (rather than this schools arbitrary placements).

So, what grade/reading level would you consider a book like Green Eggs and Ham? FWIW, DS is reading other books around the same length (the tag reading books minus the tag pen) slated for 5-8 yr olds (according to leap frog), as well as others I would consider similar to GE&H.