Aloha – When I think of Isaac Asimov I immediately think of the Robot series and his Foundation series. Excellent books, but pretty heavy reading. My favorite Asimov novel is Pebble in the Sky, which is still not what I would consider Middle School Reading. Many people are unaware that he also wrote a delightful juvenile science fiction series about David Starr, better know as Lucky Starr. I found the entire series in the Kinokuniya bookstores in Japan (along with a number of other early science fiction series). They filled the hour long train home each night with adventures that took me far from the crowded trains.
Robert Heinlein wrote twelve juvenile science fiction books between 1947 and 1958. I found eleven of the twelve totally engaging, and yes I did read all of them while in Middle School. Going back, I do find a few are starting to date a bit. But I still love Farmer in the Sky, which I believe was originally done as a serial in Boy’s Life. Tunnel in the Sky is a fascinating turn on Lord of the Flies. The Red Planet and Between the Planets is a fully engaging pair of novels that begin to connect the Solar System eco-system. But as I mentioned in a earlier post, Citizen of the Galaxy remains my favorite.
I’m not sure how I’d rate these two great authors total works to total works, but as Juvenile Science Fiction authors I believe Heinlein in the clear winner.