(Cat actually wrote this review a month or two ago and forgot to post it)
"The Heroes of Olympus" is a new series of books about Camp Half-Blood, like in the Percy Jackson series (which, by the way you should read first) and the greek demi-gods and that whole situation. This time, the story does NOT surround Percy, Annabeth, and Grover. (Although I'm not gonna lie, you're going to get to them :P they're a part of it too, it's just not entirely about them!) Instead, the lead characters are Jason, Piper and Leo.
As the book begins, Jason literally wakes up (with no recollection of anything, let alone how he got there) next to a 'very pretty girl' Piper, who he comes to find out is supposed to be his girlfriend. His best friend, Leo, is also there. Apparently, him and his friends have all participated in criminal activities and are now stuck in a school for juvenile delinquents. They all have different backgrounds, personalities, and reasons, but they all ended up in the same place. Of course, you automatically know they must be half-bloods/demi-gods, because this just doesn't happen to normal people, especially when they're on a 'field trip' and are attacked by greek monsters and...
To find out what else happens, pick up "The Lost Hero". I thought it was a great book! I think I almost like it better then the original Percy Jackson series. It's a bit different, especially in style. The book is quite a bit longer then most of the Percy Jackson books, and also, the story also switches perspectives every two chapters between Jason, Piper, and Leo, which I thought worked really well for this book. It was exciting and interesting, and walked perfectly in the middle for me of being too much like the Percy Jackson series and feeling like you're reading the same thing, and it being too different. :) You should read it!