Building a model bridge allows students to employ and observe several engineering principles in action. When building a bridge with Popsicle sticks, you should first sort through your supply and remove any bent, twisted or warped sticks. Using only straight, whole sticks will ensure the structural strength of your bridge. You can start by simply creating your own bridge and seeing how it turns out or you can research common bridge designs and why certain designs work better than others. After creating your own Popsicle stick bridge, add weight to it in the form of a small rock and see what happens. If you think you can improve your original design, build a second bridge and compare the durability of the two bridges.
Mechanical engineers spend years in college learning about forces in nature that affect their work. This project tests the effect of natural forces, such as air resistance, on non-static products. Cut a plastic bag into an octagonal shape, then cut a small hole near each point of the octagon. Loop a piece of string through each small hole. Tie the ends of the strings to a small weight, such as a small action figure or a light rock. Drop your homemade parachute from a high spot -- by standing on a chair, for example -- and observe its fall to the ground. Try different variations of plastic bag parachutes, such as different shapes and sizes, and record the effects and speed of each model.
The inclined plane, the lever, the pulley, the wheel and axle, the wedge and the screw are known as the six simple machines. They are so named because each uses a single, basic force to set a weight in motion. Simple machines are vital in mechanical engineering, as they often are components of products mechanical engineers are asked to design. For this project, students conduct research on each machine, creating six small reports detailing what each machine does, what forces it uses and some examples of common machines today that employ each simple machine.
Mechanical engineers must consider types of energy and the possible effects energy can have on instruments and buildings they design. This experiment delves into the topic of energy by recording differences in rubber band stretching and distance traveled after its release. On a large patch of cement, draw a chalk line at your toes. Stand just behind the line, draw a rubber band taut with your fingers and shoot it. Draw a line on the chalk where the rubber band landed and label it No. 1. Repeat with up to 10 bands, varying how tight you pull it before you shoot, how high or low you shoot it and anything else you think might affect the distance traveled. Record on a piece of paper your technique for each trial and record a measurement of how far each rubber band traveled.