More to explore:
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Fun activity for toddlers and babies using contact paper
Small World Play: Cardboard Box Town - What a fun idea!
Cardboard box tutorials - hours of fun
cardboard box houses
25 Fun Ideas for a Cardboard Box
Toddler Rainy Day Fun Activities
Cardboard Crafts- Easy Bulldozer Blade DIY Toy for kids made from a cardboard box
How to make a traffic light out of cardboard boxes...love this. Also how to make cardboard car, gas tank, etc. Fun site.
cardboard box castle
cardboard tubes + box = hours of fun!