The39Clues Website Poster Image




Absorbing mystery game reveals clues and yields prizes.
Popular with kids

What parents need to know

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The homepage contains a sizeable plug for the book series and cards, which kids also need to purchase to get the full experience.

Drinking, drugs, & smoking
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Parents Need to Know

Parents need to know that this site is part of a game that combines The 39 Clues Scholastic
books and collectible cards to solve a mystery. Registration is required to play and prizes are awarded at different stages.

What's it about?

As the online companion to The 39 Clues mystery book series, THE39CLUES.COM provides missions for kids to discover clues to the secret of the fictitious Cahill family's power. Each book in the series comes with six cards and adds another clue to the mystery. The cards give you leads, which you can use on the Web site to track down information and reveal more clues. The site also features several contests, including $500, $250 and $1,000 giveaways for players who participate.

Is it any good?


The book-card-game combination is an interesting idea and should get kids excited about reading. And there's no shortage of information to read on the site: Kids can check out everything from secret documents to historical recaps. The inclusion of real characters and events along with the Cahill mythology is another nice touch. The more kids get involved in the mystery, the more history they'll learn.

But hunting for clues is no small task -- and kids have to be willing to invest some serious time (and parents, money) to crack the case. In addition, not only do some of the online tasks take awhile to complete, the books are being released through 2010, which means the mystery won't be solved quickly. However, if your junior detective has the patience, the investigation should be a blast.

Families can talk about...

  • Families can talk about games that use a variety of media types to play. Is the mystery (and the prize) compelling enough to sustain your interest? Do the different play modes (books, online, cards) add to the game and increase interest -- or are you just in it for the money?

Website details

Pricing structure:Free

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Teen, 13 years old Written byTeamGale101 April 5, 2015

A fun site!

I think it's a really cool site! It teaches kids about history, and perseverance. They use problem solving skills to figure out the game. There is a forum, however, so if you are uncomfortable with :internet people", I suggest you don't use this site.... but if not, IT'S BRILLIANT!
What other families should know
Great messages
Too much consumerism
Safety and privacy concerns
Adult Written byfarrell1 May 22, 2009

Fun Fun Fun

Omg this is so fun! I have an account. I can't wait for some new videos, new books, and new cards
Adult Written byhinkpink January 25, 2009

Fun But Stupid is a fun website because you get to be a part of the story and can play fun games. The downside to this site is that it's so sad how in today's world, we feel like we have to attach the internet to a book. I feel like books should just be for reading and the internet should just be for the internet. This webstite tells you that you can win prizes but it's virtually impossible unless you spend your whole life playing a stupid game on the internet, trying to get a high score.