Bears made with pompoms and felt look very nice and are simple to make with a glue gun (lo-melt, I recommend!). They are light to hang on a tree.
Fun foam is another neat, light weight material that is simple to make bears (or anything else out of!).
If you wanted to go hog wild, you could buy small already stuffed bears and make uniforms for them with material and felt, and a glue gun. Sewing would not be necessary and accessories might be fun to come up with. Backpacks, tents, sleeping bags, little program books, and small bags to carry them in. I have a friend who takes teddy bears and jazzes them up with lace and other neat things. I have one that I bought for my husband, that has my friend's mother's pearl earrings in her ears! (Don't ask why I bought my husband a teddy bear - however I will say one thing - for a switch I managed to surprise him!!)
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