This terrible trio loves to hang out around dark and mysterious places — like your kid's backpack.

For all three charms, fold an 8-inch piece of pipe cleaner in half, then push the folded end through a 1-inch Styrofoam ball. Attach a key clip through the pipe cleaner loop as shown, then tug the pipe cleaner to pull the clip snugly against the ball.
To make arms for Backpack Drac or Mini Mummy, twist a 4-inch piece of pipe cleaner tightly around the body. For Jack o' String's arms, knot the ends of two 4-1/2-inch lengths of jute twine together, then tie the doubled section around his body. Fold the ends of the pipe cleaners for hands and feet.

Cut lengths of embroidery floss, knot them around the charm's body, and wrap them as shown. Before covering the head, dot the ball with clear gel tacky glue. Also smooth a small amount of the glue over the hands and feet to prevent any unraveling and to secure any loose ends of floss.
Glue on googly eyes and other decorations.