What You Need: Flat cardboard, rectangular cardboard box, wrapping paper tube, scissors, glue and rubber bands.
How to Do It: Cut a guitar-shaped facade with a large hole in it out of a flat piece of cardboard. Glue to a small rectangular cardboad box with the front cut off so the hole on the facade is not obstructed. Cut an X into the top of the box, pressing in the flaps that are created so you can insert a wrapping paper tube into it as the neck of the guitar. Let the cardboard tube protrude into the body of the guitar for stability, and add glue to the pressed-in X flaps to secure the tube to the box. Cut short slits in the top and bottom of the guitar-shaped piece, and loop rubber bands around them for strings. Finish the head of the guitar's neck with an appropriately-shaped piece of cardboard, slotted into the flattened end of the cardboard tube. Mousse your kid's hair into a mohawk and let him rock out.