
Play and Grow is an amazing blog by a Russian architect that has a passion for making handmade cardboard toys for his little girl. The site is filled with great diy tutorials for upcycling cardboard into early learning toys.
A few favorites:

DIY Geometric Sorting Board
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A cardboard version of the classic geometric sorting board.

DIY Developmental Toy
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An early learning developmental toy made from a diaper box, knitting needles, a doorstop, and paper.

DIY Steamship Pull Toy
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A cardboard pull toy made from a diaper box.

DIY Cardboard Train
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A cardboard train made using a diaper box and boxes from old toys.


DIY Mini Geoboard
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A cardboard version of the classic peg/pin board toy used to make shapes, patterns, letters, etc.
Visit Play and Grow for more cool projects & tutorials!