Much of it touches upon favorite tropes in our culture. I wonder why our culture has such an obsession about young girl characters that are excitable and have wild imaginations. LIke Anne of Green Gables, she is raised by an older couple who aren’t her parents and she gets in trouble with a crotchety old neighbor lady.
There have been many fictional works (both books and movies) spawned off of the original books. In particular, I enjoyed the movie Return to Oz and the tv series Tin Man. I also just watched the musical Wicked and thought it well done.
Of course, when The Wizard of Oz is mentioned Judy Garland immediately comes to mind. She does a good version of Somewhere Over the Rainbow, but here is my favorite version.