This article is about the Mark of Athena (sign). You may be looking for the book.
The Mark of Athena, is the path that Athena made for her children to find her sacred statue the Athena Parthenos which was stolen by the Romans in Ancient Greek and Roman times. Athena, picks only a few of her best children a century, the smartest and the most clever. She gives them a coin, to represent Athena and her vengeance.
The purpose, is to avenge Athena's humilitation from being a major Greek goddess, and turned into a minor goddess by the Romans. They took her statue, after they defeated Greece and hid it away, where most of her power was trapped. She sends her children, out looking for it, with The Mark of Athena to guide them.
A child of Athena's greatest challenge is the Mark of Athena, if they are chosen. They must have the wits, the strength and the speed of they are to survive which no one had except Annabeth Chase.
In the end, they know that they will have to challenge, their greatest enemy, Arachne the huge immortal spider.
The Mark of Athena (book)Edit
The Mark of Athena book, has a link above at the top. In short summary of the end, Percy Jackson and Annabeth Chase fall into Tartarus after freeing the Athena Parthenos and defeating Arachne. Annabeth, had been chosen by her mother to free the Athena Parthenos, avenging her mother and succeeded in doing so.