i am looking for a very light weight material to construct my hull. i am working on a scale model of the SMS Dresden. does anyone have any ideas... ?

You might try 1/4 ply ribs and with 1/32 by 1/32 stringers covered in two layers of 1/32 birch ply 1/2 inch wide strips. The first layer would run diagonally to the stringers. The second layer would run the opposite direction. 1/32 ply easily twists and bends and also is readily glued with CA. Wood dough or spackel can be used to fill in any gaps between planks. It works very nicely. I have tried it on two scale boats 1/20, 1/144. The hulls are strong, fair, and very light.

Dresden, what scale and what purpose are you building your model? And how truly "light" does it need to be? For example, if you were building a 1:144 scale model for actual RC naval combat, I'd say either plywood or fiberglass hull and balsa skin as per club regulations. If, on the other hand, you were building a 1:200 scale model for display purposes only (no RC, does not need to float) I'd say don't worry about weight and use whatever material you want. Or if you were building a 1:72 scale model to fill with helium and use at your local RC airplane club, I'd recommend cardboard and paper and say "good luck". In short, give me a bit more information so I can help you better.