A great website that is fun to do, along with reading the books. I think this is good for kids 7 and up, IF they can do a good amount of reading. For fair readers of 7 or younger have a older sibling or parent to help; or better yet wait a while for them to have better reading skills, so that they can read. Also, there are a lot of stuff that involves the cards and books you have to buy, and some of the later missions get more difficult and stressful.