We can give a huge "thank you" to American Home School Publishing for reprinting many of the works of Caroline Dale Snedeker. It appears she did not begin writing until her 30's and from then on produced numerous books that are set in ancient history, filled with adventure and excellent writing. Four of her books were set in ancient Greece, including The Spartan. The book was originally written for adults, but it was not ultimately well received until it was rewritten for children. It is most appropriate for those ages 12 and up.
The Spartan tells the story of a young boy named Aristodemos. It begins with his mother delivering him from Athens to be raised by an uncle in Sparta after she is widowed. Young Aristodemos is less than enthusiastic about his new life. He ultimately trains to become quite a fighter and fights in The Battle of Thermopylae. While 300 warriors around him perish, he survives, much to his disillusionment and disgrace. The balance of the book details his experience of being cast out by Sparta for his battle survival, and how he labors to redeem himself.
This is fabulously written! At first glance, I thought I would be put off by the ancient dialect, such as in the question: "Art thou wont to be called beautiful?" I found, however, that the story was so well written that the occasional awkwardness was not bothersome, especially when set off with prose like this: "There was more of widowhood in his young face than in his mother's. He had looked on death, he had lost his own; and his eyes bore in them a look of inner awakening that does not often come to one so young." Your whole family will enjoy this adventure filled read-aloud. It is perfectly suited for middle school readers and above and will complement your ancient history study nicely.