What is a good light weight material for Kites?

For cheap toy kits you can use large trash bags for the kite cover, thin Ash or Maple sticks (cross braces) for strength, and butcher twine for the string. For mid to high end kite materials, kite cover materials: Japanese paper, ripstop nylon, tyvec (a plastic coated paper), or mylar. For stick material: there are many lightweight, high strength metals out there but, for strength to weight ratio, a carbon fiber composit stick or tube would be your best bet. For your string or line there are many to choose from: strength to size an weight ratio, nylon seems to be the best.