Clark College -- The main challenge was to build a working prosthetic arm. Middle and high students from throughout Southwest Washington turned out at Mathematics Engineering Science Achievement (MESA) Day on March 23 at Clark College to show off their designs. They'd already written technical papers, created displays and made oral presentations of their designs. On MESA Day those designs were tested and rated in a number of ways, from accurate ball throwing to an assessment of the amount and complexity of equipment used. Other projects included building a boat out of clay and creating a parachute that would preserve an airborne egg.