Most economists have long advocated that the 'dismal science' ought to be included, somehow, in high schools. Why not settle for just the basics of the National Income and Product Accounts and the basic outlines of how and on what money is spent, both public and private?
Anyway, since Mankiw is pushing his own textbook, most likely, for the job, Edmund S. Phelp's "Political Economy: An Introductory Text" is like a breath of fresh air compared to the staid stuff that often passes for economics education.
For a great laugh (I mean apart from the IEEE humor I posted), try this:
Mankiw's "Principles of Economics", translated