Jason is a camper at Camp Half-Blood. It is unknown who is his godly parent, but it is presumed to be Aphrodite, Ares, or Hephaestus, as they were the only cabins with unnamed campers who participated in the game in The Titan's Curse. His surname remained unknown.
During a Capture the Flag game against the Hunters, Thalia Grace tells Silena Beauregard to take Jason and a demigod named Laurel to lead a decoy run because those two are their best runners. Jason is never mentioned after this.