We are recycling and creating this month with EGG CARTONS! I bet you have a bunch of it after Easter, right? We made mache from egg cartons, molded it and painted it! 
An egg carton already have the ingredients for mache-ing(if that is the word). You don’t need to add any glue, although when you add the wet cartons to the mold, you have to compress it tightly otherwise it just crumbles apart(see the animal molds we did).
First, we tore the egg cartons into small pieces. This was hard work and great fine motor and hand strength practice. Then we added water until it was all mushy. My SPD child loved this part!
We left it to soak for a few(4) hours. Them pressed put most of the water and shredded I some more with a handheld whizzer. Then we added it to silicone molds.
Compressing it properly helped to keep the shape when dry. My daughter did the animal shapes, as you can see, it did not hold its shape well because it was not compressed well. The big shapes were not dried enough, I think, that is why the edges were crumbly.
Then came the painting part! We were careful in painting this, since it was a bit delicate, but it was fun. The end product came out so pretty!
Next time I will add a little glue to the mixture just before we add it to the molds to see if it is less crumbly and delicate. But do try this as a frugal crafts activity with a great sensory component!
Do pop over to see these egg carton recycling projects:
Intrinsic Hand Strengthening Activity by Sugar Aunts
Flowers by The Gingerbread House
Daffodils by Nemscok Farms
Space Station by Peakle Pie
I had no idea you could do papier mache with egg cartons! We so have to give this one a try!