I'm a full grown adult, but I still think about the book, The Giver by Lois Lowry frequently.
I remember reading it in middle school and seeing how sad the monotony of the restricted world was. How cruel people could be acting on orders and/or without their hearts. How educating yourself with different experiences opens your eyes. Among other great undertones and lessons.
I hope to introduce all of my nieces and nephews to it in the future.