These books are another connection to my childhood. I didn’t read them growing up, but the Mowgli stories of Rudyard Kipling’s The Jungle Book and The Second Jungle Book form the foundational mythos of Cub Scouts. In fact, Baden-Powell asked Kipling for permission to base the Cub Scouts upon his work.
My interest was primarily in the Mowgli stories. The idea of the “noble savage” runs strong through the text, with Mowgli becoming stronger and tougher than any regular man thanks to his unique upbringing. His nobility and moral superiority come from an upbringing under The Law of the Jungle which is called “by far the oldest law in the world” and “as perfect as time and custom can make it”.
As he becomes an adult, Mowgli eventually outgrows the jungle and must leave to find his way in human society. That fits the age-bracketing on a Cub Scout Pack rather well - eventually things have to be let go to grow beyond them.