User blog comment:Darkcloud1111/Official "The Sea of Monsters (movie)" Discussion/@comment-6951062-20130327190539/@comment-3146930-20130327193614

In the books, Percy is only 12 years old. In the universe of the movie, it is established that the characters are in High School (at least the ones that go to school). Plus, 20+ year old people have been playing teens in movies since forever, I mean look at Grease.