An entertaining read, but with a premise that might make some readers uncomfortable.
Plot
When a game of dodgeball suddenly turns into a battle with man-eating monsters, twelve-year-old Percy Jackson flees to the safety of Camp Half-Blood, a haven for the children of gods and mortals. Unfortunately, all is not well at the camp. The protections on the borders have begun to fail, and may fall completely if Percy and his friends can't retrieve an ancient treasure, the Golden Fleece.
Morality
For the most part, the characters behave in a morally consistent manner. Percy lies once to spare someone's feelings, and the children lie to trick one of the monsters.
Spiritual Content
The series is based on the premise that the ancient Greek gods are still alive, so phrases like "thank the gods" are present. Percy prays to the gods and offers a food sacrifice to his father Poseidon (a portion of his dinner, nothing gory). At one point a character seeks guidance from an oracle, and Percy continues to have semi-prophetic dreams, due in part to an empathis connection created between himself and another character.
We also meet the sorceress Circe who is depicted as a villain.
Violence
Percy and his friends battle several monsters, but descriptions of the battles are rarely violent. The children travel on a ship crewed by dead Confederate soldiers. At one point, a father threatens his child if the child fails in a quest.
Drug and Alcohol Content
Dionysus, the Greek god of wine, is the director of Camp Half-Blood, but does not drink during the course of the story.
Hermes gives Percy some magical vitamins which help the children to resist magical enchantments and remain themselves.
Sexual Content
One character gives another a kiss on the cheek. We are told that some fish are going off to spread gossip about Percy and a girl they see him with.
As in the previous volume, the plot is dependent on the concept that the ancient Greek gods are still alive and periodically mate with humans and other beings.
Crude or Profane Language or Content
There is one mention of a character's past vomiting, but he manages to keep it together in the book. A character says d-m-.
Conclusion
This installment in the Percy Jackson series is as diverting as the first one, with plenty of adventure, humor and plot twists. I especially enjoyed a fresh look at the motives of a former antagonist: Clarisse, daughter of Ares. I'm glad that the author chose not to keep her as the flat character she was in Book One, but to show us a little more about what makes her tick. The primary drawback to this book is the same as its predecessor: it focuses on heroes born of extramarital relationships.