Turn the first milk jug upside down, and cut two slits in the top (the base of the jug). Lace a piece of wire through the slits, and twist the ends together to hang the skeleton. On the side opposite the handle, glue recycled bottle tops to make eyes, a nose and a mouth.
Hold the second jug right-side up. On the side opposite the handle, cut two parallel sets of slits going down the jug about 1/2 inch apart. The slits should be 2 to 3 inches wide. Make a ring of hot glue around the spout of the first jug and attach the spout of the second jug -- positioned so that their handles are aligned on the same side. Hold the spouts together for at least 1 minute to allow the glue to dry.
Trace a semicircle around the top of the handle of a new jug. Cut around the semi-circle and under the handle to detach it from the carton. Detach the rest of the handle from the jug at its base. Repeat with a second jug.
Glue the handles to the "torso" section -- on either side of the ribs at the top, rounded corners of the milk jug. The handles will serve as the shoulders and upper arms of the skeleton.
Cut a new jug horizontally around the middle, and discard the top half. Invert the bottom, and rim the flat top with hot glue. Press the jug into the bottom of the torso section of the skeleton and hold for at least 1 minute to allow the glue to set. Punch holes in the sides of the jug -- at the front of the skeleton -- to attach legs, using the hole punch. Punch one hole on each side.
Trace long bones on the remaining jugs. You will need a humerus (the long bone of the upper arm); radius and ulna bones for each arm; and femur, tibia and fibula bones for each leg. Make the long bones approximately the length of the milk jug. The humerus and femur should be 2 inches in width, while the other bones should be skinnier -- about 1 inch wide or less -- to approximate their real dimensions.
Punch holes at the top and bottom of each bone. Wire the humerus to the handle shoulder, the radius and ulna to the humerus, the femur to the hip section, and the tibia and fibula to the femur.
Have your child trace his hands and feet on leftover scraps of milk jug. Cut out the pieces, and punch one hole through the palm of each hand and through the heel of each foot. Wire the hands and feet to the radius (the thumb side of the forearm) and ulna (the pinkie side of the forearm) and tibia (the inner/larger of the two lower leg bones) and fibula (the outer/smaller of the two lower leg bones) respectively.