Cut the hook and wire twist portion off of two wire coat hangers using wire cutters and discard those parts as they will not be needed. Stretch the hangers until both are completely straightened and then trim so both are the same length. Hold these two straightened wires together and bend them both at the same time to form the shape of a car if looking at a car from the side.
Cut the hook and wire twist from the third coat hanger and discard. Stretch this hanger until straight. Have someone hold the two previously formed wires about one foot apart and then connect the front bottom sections of the car sides to a straight piece of wire. Use needle-nosed pliers to connect this front trace to the front ends of the two side-view pieces by forming loops to secure the parts together. Cut off the long remaining portion for use in making more braces.
Form another brace connecting the two side pieces together at the windshield area. Run a brace between the two side pieces across the bottom of the front windshield, then another at the top of the windshield. If necessary, use some duct tape on the joints to prevent them from sliding around on the side-view wire frames, using the tape anywhere else further reinforcement is need to hold the car together.
Cut more hangers as needed and form braces at the top and bottom of the rear windshield and one at the top rear portion to form the lip of a trunk. Add a brace to at the bottom to form a bumper and, finally, create two wire braces across the center of the bottom of the car frame. Use only the minimum necessary wire braces to form a "boxed" car body out of the wires, leaving plenty of empty space where the pinata will break open when hit with a stick. Connect all brace ends with the needle-nosed pliers and small portions of duct tape.
Cut newspapers into long strips about 1 inch wide and 1 foot long. Cut plenty, as these will be soaked in the adhesive mixture and laid over the wire frame to form the shell of the pinata. all areas must be covered.
Pour 1/2 cup of water into a bowl, then add 1/4 cup of corn starch and one large bottle of white school glue. Mix thoroughly and add more water if necessary until the mixture has the consistency of corn syrup. Use this recipe to make more adhesive on an as-needed basis until pinata is complete.
Dip each strip of newspaper into the adhesive mixture until thoroughly soaked. When removing the strips from the bowl, pinch the strip gently between two fingers and pull the strip through the fingers to wipe off excess glue, allowing it to drip back into the bowl. Layer newspaper strips all around the car frame until completely covered Perform this step until three to four layers of newspaper strips have been applied to the pinata.
Allow the newspaper shell to dry until hard. While the shell is drying cut your chosen colors of craft tissue paper into 1 x 1-inch squares.
Wrap each tissue square around the eraser of a pencil, placing the center of each square over the eraser and pulling all edges upwards against the pencil. Dip the tip of each piece into the adhesive compound and stick them to the shell of the car body. Use different colored papers for the various parts of the car, completely covering the car as desired.
Cut a hole in the top of the car body shell and fill the pinata with candy and party favors, then layer it closed with just enough newspaper strips to conceal the opening, then finish by covering with tissue paper if desired.