The Giver by Lois Lowry: This isn't appropriate for young kids, but I consider it a must-read for all older kids. This story will open up their minds, make them consider their world from a meta-cognitive viewpoint, and help start conversations about our purpose in life, kindness towards others, and making decisions for ourselves. It's a beautiful, important book.
The Complete Anne of Green Gables Boxed Set (Anne of Green Gables, Anne of Avonlea, Anne of the Island, Anne of Windy Poplars, Anne's House of Dreams, ... Rainbow Valley, Rilla of Ingleside): L.M. Montgomery: