Agree with GeoFizz on the books mentioned, especially! The Number Devil; great read, and throw in some very fun Math videos such as those from Vy Hart! (sometimes it is great to just see a picture of a young woman doing math, with BALLOON animals, to open a kid's eyes).
http://vihart.com/doodling/
I love 'Stars', and the mobius strip video. Cool stuff.
http://vihart.com/balloons/

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