Here's from my 11 year old daughter first. She says: "It's very good. I like that it has mysteries you have to figure out. The main characters care for each other and rescue each other. It's very mysterious. I love it." Mom says: "I like it a lot- and I am enjoying the mystery and intrigue just as much as the children. However, I could do without the harsh or belittling language used by most characters. I also hope that the main characters use their goodness to triumph in the end (the end of the series), because that is how they will be good role models-- not by sinking to the level of their adversaries. But overall- it's highly entertaining and even a bit educational."

My 9 yo son really enjoyed this book, and together we really enjoy playing on the website. I do agree that all the marketing/merchandising surrounding this series is terrible (typical Scholastic) but to their credit you don't have to buy the books and/or cards to participate in the website/game - we got the book from the library without cards and are having a blast playing on the website without any cards in hand/$$ spent. So kudos to Scholastic for not making it impossible to be in on the fun without any cash outlay. And the incidential learning about historical figures in each of the family branches is really interesting and not often found in games/books for this age group. FYI my older son (turned 13 days ago) read the book and found it quite boring/immature, particularly compared to Rick Riordan's other works, the Eragon series, etc. So even though the target age for this book is 8-12 I think it more skews to the younger end of that spectrum (and this from a parent who is fairly protective of what my kids read, i.e. the 9 yo has only read the first 3 Harry Potter books). Might be good though for a reluctant reader in the older end of the range.