This upcycled cardboard building set is a terrific open-ended toy that won't cost you a cent! All the materials come from the recycling bin.
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DIY Cardboard Box Toy House - Little Red Window
Trash Garbage + Tires + Boots + Empty Cans + Papers + Recycling + Recycled + Cardboard Furniture DIY Recipes + Garbage bins + Oil barrels Bundle Set - elymbmx
Homemade Cardboard Construction Set - Happy Hooligans
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