One thing would be soaking the spaghetti in water until the surface of the pieces gets soft. Grab 10-15 pieces and squeeze them together. There is a sort of "glue" on the surface of the pieces that will stick them together. Using the gumdrops as connectors, make a bunch of triangles, and then find a way to stack them up to whatever height you can. Also one other thing, the shorter the strands of spaghetti you use, the harder it will be for them to break under compression.