Make a shield
2 pieces of cardboard, tape, scissors, strips of material
Sketch a rectangle onto one sheet of cardboard. Cut out the shape. Lay it on top of the other piece of cardboard, trace it, and cut it out. The shield will be more durable if the corrugation ridges of one sheet run horizontally and the ridges of the other one run vertically.
Glue the two cardboard rectangles firmly together. Allow the glue to dry completely, then reinforce all of the edges with strips of duct tape.
Have your child decorate the front of the shield. Markers, crayons, paint, glitter, colored paper cutouts, shiny buttons and uncooked pasta all make for great decorations. Allow the shield to dry completely.
Measure your child's fist and the widest part of his forearm. Use the two strips of canvas or heavy denim to form circles large enough for him to loosely slip his fist and forearm completely through. Securely duct-tape these arm straps to the back of the shield where you made the marks.