Designing and building mechanisms that can resist the harshness of environmental phenomena such as water and wind is an important part of mechanical design. A lesson geared toward early teens demonstrating this fact should raise a practical issue in basic mechanics and let students deal with that issue. For example, lighthouses tend to be subjected to strong winds and must therefore have strong wind resistance. An example project along these lines would be to have students design miniature lighthouses with the goal being that the lighthouses are wind resistant. Students can use the “cool” setting on a hairdryer to test their lighthouses.
Engineers design objects such as buildings and bridges with structural strength in mind. Early teens can build simple structures that attempt to achieve a set goal, such as holding a gallon of sand. Such a project will show students how different shapes and designs can vary in strength.
In engineering, practicality is everything. Structures often need not only be strong, but must be light in weight as well. For a project that demonstrates this fact, instruct students to design simple objects that vary in weight, and then test the strength of these objects. The results of such a project should compare the weights and strengths of the objects in terms of percentages. For example, a plywood structure with holes in it may be 80 percent lighter than the student’s other plywood structure; however, the student may find that the lighter structure can hold 90 percent of the weight that the heavier structure can hold, implying that the lighter structure is more practical and efficient.
Students in middle school and high school begin to become competitive academically. You, as an educator, can apply this phenomenon by holding a design competition. Let the students design structures under a set of rules. In short, this project is to prepare for a competition in which students’ designs will be compared. The competition can emphasize an idea that you wish students to internalize, such as triangles being the strongest simple shape in mechanics.