How can I build the lightest tower with a platform that holds the most weight, with the following materials?

Question

I need some tips. The tower has to be about 75cm tall and 30cm long and 30cm wide. It needs to be as light as possible btu be able to hold a lot of weight. I have some tools (ie. knife, glue gun, scotcch tape, ruler, paper, scissors, etc.) and I also have wood, foam, straws, and fishing line.

Please help, what are some strong structures?

Answer 1

Unless you're allowed to connect the tower to the ceiling, the fishing line is not going to help you at all, because it can only sustain tensile loads.

The tower should use truss construction - beams connected to nodes.  Don't leave open rectangles; use only closed triangles.

Since the bottom of the tower must support the full weight, while the top supports less, the tower should be somewhat narrower at the top.