Catapults, sling shots, trebuchets (tre-boo-SHAY), and other throwing machines have been used as real weapons for at least a thousand years, and as toys for centuries. We cannot know who invented them, but in most cases, it was engineers, not scientists, who developed and refined them over the years. Engineers are practical people who fit materials together in clever ways to do a particular job. Sometimes, scientists explain how and why it all works, and they may suggest changes of design based on their theoretical knowledge. But even then, it always goes back to the engineers to work out the bugs and prove that the ideas are really on target.

In the Trebuchets project as in all other projects in the Design It! series, children act principally as engineers. This means that they are problem solvers. Children are not asked to invent a machine from scratch nor are they expected to understand all the science that makes it work. Instead, they are given a working design and some appropriate materials and asked to engineer a successful and, perhaps, improved machine. The target age group for Design It! projects is 8-12 years old but this Trebuchets project has been successfully completed by middle and high school students also.

As students of all ages work through the challenges in this project, they will also learn about experimenting, testing, making observations, asking questions, and explaining what they have done and why they did it the essential elements of critical thinking and the inquiry approach to engineering and science.