Rain Sticks

Use a pencil to draw a spiral, from one end of the cardboard tube to the other.
Hammer nails that are 1/4 inch shorter than the tube's diameter at random intervals along the spiral line.
Cap one end of the tube with duct tape.
Put some unpopped popcorn, beads, dry beans, pebbles, seeds, gravel, rice or other dry filler into the tube.
Cover the open end with your hand and test the sound by turning it upside down.
Experiment with the amount of filler for a sound you like. When you're satisfied, tape up the other end of the tube.
Cover all of the nail heads with contact paper or masking or duct tape.
Decorate your rain stick. Try construction paper, stickers, paints or markers.