Robotics hobby kits for kids?

My child wants to learn how to build a functioning robot. I'm delighted, but haven't been able to find a beginning robotics kit for kids in toy stores or even educational stores. Does anyone know where I can find this? Is there a web site that specializes in this sort of thing?

Here is something that will get you started
http://www.amazon.com/Ultimate-Robot-Kit-David-Eckold/dp/0789479451
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