Cute idea! 
                                      Snowman Poop

Put tiny marshmallows or white packing peanuts into a plastic bag, accompanied by this poem:
                                        Santa checked his list not once,but twice
                                        He found that you've been naughty, not nice
                                        Since coal is so expensive,Here's the scoop
                                        He's filled your stocking with snowman poop!

                                      Reindeer poop

Same as above but use chocolate covered raisins, plain raisins,malted milk balls etc. Use the same poem as above,just change "snowman" to reindeer.