Book suggestions for a variacous 9 year old (probably HSP)

I can't get to the library fast enough for this boy. His reading level is hovering between 4th and 5th grade. He has read: The frank Einstein series A Rover's story (his longest solo read) Chris Grabbenstein (currently on the James Patterson/Grabbenstein books) The Wild Robot Every graphic novel we've said yes to. Most Dahl [...]