For an engaging and dramatic geometry unit, my students construct large models out of tightly rolled newspaper struts. The struts must be clipped at the ends where there are weakest and it's best to use full format newspapers and roll them tightly from corner to corner. I use masking tape to make the connections. I've been able to construct tetrahedral prisms and 3-D Sierpinsky prisms up to eight feet high. Making measurements of height, slant height and base area is a challenging and interesting problem that makes the study of surface area and volume more of an active concrete exercise.