Paper lunch sacks are great party favor bags. Just use some fun ribbon to close the bag with all your treasures inside. It is inexpensive and kids don’t really care about how decorative their bag is anyway, it is what’s inside that counts! If you would like, you can paint or otherwise decorate the outside of the bags prior to filling them. Even better, you can have the birthday boy or girl decorate the bags as a gift to his or her guests.