3.75 stars

Camp Jupiter Classified: A Probatio's Journal is a nice background story on the Roman camp. The story follows Claudia, a descendant of Mercury. The story is set after the event of The Blood of Olympus but possibly before The Trials of Apollo since it does not spoil any of Apollo's adventures in the series but it could also happen simultaneously with the first few books in the series. Although you might appreciate a character here and there more after having read The Tyrant's Tomb.

I liked Claudia's journal, especially since it gives us more of a background on day to day life inside Camp Jupiter. It is very different from Camp Half-Blood so it is interesting to see how the probatios, legionnaires, centurions and praetors are living and training together.

The book is illustrated as well. The illustrations are beautiful and I quite like the art style.

I recommend Camp Jupiter Classified to those who want a bit more background on Camp Jupiter and want to go on a mini-quest to save the camp.