add book codes
the books will only give you ten clues so the cards fill in the gaps along with the 39 clues website
Once you get the code, go on to the 39 clues website and create an account! After you do that that click MY CARDS and enter the code.
Scholastic and i think some of the authors of the books helped.
It is possible to get all of the 39 clues in a day, but you would have to add a whole lot of cards, but currently as of June 1st, only 37 clues are available.
You have to make your own account on the 39 clues website, then look for the code on the card, click add card, and enter the code.
the boy in the 39 clues books is called Dan cahill and the girl is called Amy Chaill
only 39 clues... hence no 41st clue
You must have all 39 clues in order to continue with the final mission. You can get these "clues" by playing the missions in the 39 clues website, buying the books and entering the code in the cards you got, and buying a card pack; Example:P4G4MPNNXP. Sorry but even I haven't done it.
You have to play all the missions and get all the books and the card packs
Buying Books
There are absolutely no cheats for the 39 clues website. AT ALL!