The Trials of Apollo: Camp Jupiter Classified: A Probatio's Journal
Suspicion falls on Claudia, the Fourth Cohort's newest probatio. After all, the mischief started shortly after she stumbled into camp. Plus, she's a daughter of Mercury, the god of thieves and tricksters.
To find out whether she's guilty or innocent, readers can delve into the pages of Claudia's personal journal. Through her eyewitness accounts, they will visit the crime scenes--a row of seats in the Coliseum, an underground aqueduct tunnel, the strange staircase at the back of the principia--and see the bizarre events unfold. They'll be right alongside Claudia when she discovers a secret so ancient that not even the lares know about it . . . a secret that holds the key to Camp Jupiter's safety.
Claudia was trained in Wolf House and has solid engineering skills, although Janice does have to give her some hints when building an arch. It's great to see girls represented in this field, and Riordan's work treats all genders equally, which is good to see.
These short books can be read out of order, since they focus so specifically on one character, and would make a great gift for young readers are smaller occasions, if they are getting the main books for birthdays and major holidays. Really, any occasion is a good one for adding more Riordan books to a collection of die hard fans, since all of the books begged to be reread as "comfort reads".