I think he's read most of the sci-fi type books you find on the teen shelf at the book store.
Thanks,
polarbear
I am going to stick to harder scify with some complex ideas and that I think would appeal to a PG kid of 11. By hard scify I mean the author tries hard to use known laws of physics and a mostly believable plot. Each work should then tell him if he wants to go further.
These stories are so funny you will throw up.
http://www.madscientistsclub.com/MSC/Home.htmlA great one by Heinlein.
http://en.wikipedia.org/wiki/Podkayne_of_MarsThis one makes you think.
http://www.amazon.com/Step-Farther-Out-Jerry-Pournelle/dp/0441785832L'Engle.
http://www.amazon.com/Wrinkle-Time-Madeleine-LEngle/dp/0440498058Some of the best scify from the 70s. Most of Niven's other stuff is a bit too much until 14 or so - but if Jerry is on the cover, the latter's Catholic roots keep the sex part out. ( Jerry still writes a blog and was a PG kid growing up in the middle of no where. )
http://www.amazon.com/Mote-Gods-Eye-Larry-Niven/dp/0671741926/ref=pd_sim_b_2Hal Clement's "heavy" stories. Not to be missed.
www.amazon.com/gp/product/B000FA5UA...IKX0DER&pf_rd_r=1RX0HV85XGRREQH0Q4BDAsimov's Foundation series.
http://www.amazon.com/Foundation-Novels-Isaac-Asimov/dp/0553382578/ref=pd_sim_b_20Greg Bear's take on the Singularity.
http://www.amazon.com/Blood-Music-G...mp;ie=UTF8&qid=1321875989&sr=1-1And this one by Vinge.
http://www.amazon.com/Peace-War-Ver...UTF8&qid=1321876032&sr=1-1-spellClarke:
http://en.wikipedia.org/wiki/A_Fall_of_MoondustAnne Mcaffrey and her Dragons are there for when he is 14.