The strongest structure...

 We did a shape test. We tryed the triangular prism. It held 14 marbles,then we  tryed the rectangular prism it held all of them.  The cylinder  too held all of them. So next we tried using books. The rectangular prism held 18 books. The triangular prism held only 9. The cylander held 33 before it crumbled. So the cylander is the strongest shape!   Quinton & Jayden