To make an effective truss it’s crucial to build it in triangular structures. You can test this for yourself by building little model bridge support pieces out of popsicle sticks.

In a spirited competition, students worked to make the most efficient model truss bridge possible. Then to test their creations, students loaded weights on the bridges until they failed.

Steel truss bridges are a common sight on roads and railways around the world, with many dating back to the late 19th and ...