I loved Newton's Cannon. By the third book I didn't like it as well but overall I liked the trilogy and am glad I read them. Very interesting.

There are actually four books in that series now, which are in my "to be read queue". The fourth book is titled "The Shadows Of God"

As for Coraline, I expect all parents will judge material they read for their kids first, I guess. :) I think a 6-7 year old would adore it, though.