My kids and I played around with making robots from assorted wood pieces earlier this year and it was so much fun! You can purchase small pieces of wood from the craft store (called Woodsies), and along with wood glue, acrylic paint and your kids' imagination you'll have a whole army of robots in no time! I chose metallic paints and finished with a coat of Mod Podge to make them look more authentic :) More pictures here.