Escape from lost island series is along the lines of "Lord of the Flies" but without the Devil worshipping. I read this series when I was in Jr. High and recently reread them through interlibrary loan at the library. Well worth the time.
In a nutshell: Evil mutants live on an island that is owned by the military (experiments gone wrong). Plane of young boys get stranded and must try to survive until someone can rescue them or they find a way to escape.
Great set of books I wish the series would be reprinted.
Series includes: Stranded! Attack! Mutiny! Discovered! Revenge! and Escape! by Clay Coleman