I agree, 'Liberty & Tyranny' is a good starter book for ages as young as 6th grade, but if your looking for constitutional liberty in action, don't waste your money on Levin's ‘liberty amendments’ book. That one is wrought with error that actually takes away liberty. There are a couple of good constitutional amendments, such as repealing the 17th amendment and congressional term limits, but when Levin wades into the area of constitutional economics & citizenship, he is utterly ignorant.
Thank you for that advice. I was considering purchasing several more of his books, even though I am a Trump supporter.