This is a shameless plug... but it's also not.
I really do believe that the most important thing right now, at this moment in time (and also always) the thing that is most missing right now, the thing that civilization itself depends upon, is independent thinking.
That's what my book, Annabel Pickering & the Sky Pirates - the Fantastical Contraption, is all about. I don't think I'm at all preachy about it, and if I've done a good job of it then you won't come away saying "well that was one fantastic book about independent thought! I'll have to recommend it to all the parents I know!" You'll come away saying "wow! What a great adventure story with pirates and air ships and anarchy and a plucky young schoolgirl! I can't wait to find out what happens in the next one!"
...but it's really about independent thinking.
You be the judge though.