Despite the cover of skulls & bones on the cover, our 10 yr old daughter loved this book and now wants to read the rest of the stories. I've been to the catacombs in Paris, and it was fun to talk about it with her (even showed her some of the pictures). She really enjoyed the mystery and suspense aspect of the book. This was a bit surprising since she still has trouble watching any movies that are remotely scary (PG-13 and up). I think anything that can make your kid excited to read more is a great book.
You really need to check these books out if you have a child between the ages of 9 and 14. My daughter just started to read them and loves them. Plus the online activities associated with these books are fantastic, we play them together and have a blast. A must read.
I've read the first 6 in the series. I love every one and I'm a mom of four. My two older boys, ages 9 and 11, really enjoyed the adventure and surprises throughout the books, especially since it's about kids. Great read for anyone ready for an action packed mystery adventure.