A Greek Temple by Fiona MacDonald

Mostly focused on the Parthenon, this book can be used mostly as a visual supplement, or you can actually read the text (I don't know if my children read it or not, they read at least some, but I don't think they read it all).  It goes into quite a bit of detail, especially for a book that has more pictures than text.  Talks about things such as temple designs, including types of columns (doric, ionic, etc), and proportions, how to build the temple, workers, tools, parts of the temple (architecture), sculptures, decorations, festivals and holidays, how different types of statues were made (clay, wax, hollow metal, etc), and more.  Very detailed, but again, more pictures than text, make it appropriate for a wider variety of ages.