Beefing up the Kids Aisle of the mental_floss Store

We're expanding the mental_floss online store and we need your help!
Specifically, let's talk about the Kids section. We're developing some new educational products for the littlest Flossers. (My side project du jour is a set of placemats that strive to make your kids smarter and, for a brief period, internet famous.)
On top of new mental_floss products, we're looking for brilliant items that already exist. What books, games and toys have taught your kids the most? These can be for babies, toddlers or older kids.
Please send your recommendations to our newest addition, Jamie Spatola (jamie@mentalfloss.com). Among other projects, she's heading up the "we should add a bunch of new products to our store" effort. And she's an amazing bowling instructor. I'm sure we'll talk more about that in the future.
Need slightly more incentive? If you suggest something great and we're able to work out a deal with the person or company who created it, we'll send you a $5 mental_floss gift card. Just be sure to email your suggestion to Jamie, as opposed to -- or in addition to -- leaving a comment.
Thanks guys!