Greek hoplite soldiers carried shields like this one. The cut out areas made the shield lighter to carry. To make a shield like this one, cut the shape out of a large piece of cardboard and paint it. Then after the paint dries, glue on metal jar lids and wooden sticks to make the pattern.
Ancient Greece!: 40 Hands-On Activities to Experience This Wondrous Age (Kaleidoscope Kids), by Avery Hart, Paul Mantell, and Michael P. Kline (1999). Gives ideas to get kids thinking, rather than step-by-step instructions.