When it comes to teaching teens about science, technology, engineering, and mathematics (STEM), hands-on experience is best. Even years later, students can still recall when they created a combustion reaction in high school chemistry class or were spun in a desk chair while holding textbooks in their outstretched arms to illustrate centripetal force in physics class. MOLA kits can serve as another memorable hands-on experience. These kits provide an interactive way for students to experience structural engineering by creating customizable and surprisingly accurate models.
The idea of a MOLA (meaning “spring” in Portuguese) Structural Model was first developed by Márcio Sequeira during a post-graduate architectural program in Brazil in 2004. The first Structural Kit (See Figure 1) was launched after ten years of design development in 2014 using a crowdfunding campaign. The kits include spring bars, joints, plates, diagonals, and bases that can realistically simulate how structural components behave in real life. Their ability to closely imitate structural behaviors was studied and validated by a series of tests at UFOP – Federal University of Oura Preto, Brazil. A bilingual manual in English and Portuguese is also included in each kit that explains the functions of different parts and illustrates how a set of modular components can be combined in countless ways to construct different structural systems. The kits are invented as a fun and intuitive way to learn abstract architectural and engineering design principles for people of all ages, from young kids to adult professionals.
The ACE Mentor Program (ACE) has been an ideal environment to use the kits as a teaching tool. ACE is a free afterschool program that brings together high school students to learn about architecture, construction, and engineering directly from industry professionals. Gilsanz Murray Steficek (GMS) has participated in ACE since 2006, teaching high school students about structural engineering, and introduced the kits to our students after participating in the 2014 crowdfunding campaign. After a brief presentation on the basics of structural engineering and three types of lateral systems: moment frames, braced frames, and shear walls, we challenge our ACE students to use the kits to build the tallest tower they think can survive an “earthquake” while using at least two different lateral systems. The “earthquake” is simulated on a rudimentary shaker table constructed from a tray filled with pencils.
The students come up with a wide variety of tower designs and even perform their own tests during the construction process to see how their structure reacts to the lateral load of, say, a student poking it. The students physically experience the differences in stiffness between the three types of lateral systems created with the parts. Some students learn the consequences of having a soft story first-hand. At the end of the ACE session, students present their structure to the class and test their build on the shaker table. Through their experience with the kits, students can easily identify different lateral systems in their structure, explain which systems provide more rigidity and why, and infer which structures might perform best on the shaker table. And, perhaps most importantly, the students yell and laugh as they watch their towers ultimately collapse in the “earthquake,” undoubtedly creating a memory that would solidify their experience with structural engineering.
The kits can also be useful for students at a higher level of education, such as undergraduate and graduate students. In undergraduate-level classes, students will start learning physics behind different types of structural elements such as trusses and frames, different types of connections such as hinged and rigid connections, different types of structural loads such as vertical (gravity) and horizontal (lateral) loads, different types of structural stresses such as axial, shear, and bending stresses, and different types of structural deformations such as translations and rotations. The kits can serve as a learning tool to demonstrate fundamental structural behaviors such as how a truss element and a frame element behave differently, how a hinged joint and a rigid joint create different deformations in the adjacent connecting pieces, and whether an element would take gravity and/or lateral loads. For graduate students who learn advanced structural theories that are heavily based on abstract mathematics and physics, it can be challenging to develop an intuition for the behaviors of complex structural systems such as indeterminate (redundant) structures. Building a 3D prototype of the whole structure and visually assessing its gradual deformation provides a powerful learning advantage. Students can develop stronger intuition for how each structural piece would deform and how that would bring about the overall deformation of the entire structure. The kits can serve as a learning tool for connecting abstract concepts learned in classes to reality. For example, in the graduate-level Structural Stability class at Johns Hopkins University, graduate students use visual aids such as the kits to understand the differences among various buckling failure shapes that are hard to demonstrate on a 2D piece of paper or a whiteboard. Moreover, creating countless combinations using a set of modular pieces can improve their structural intuition and creativity as future practicing professionals. Physically building something and experimenting with different geometric shapes can help understand why certain structures are better than others.
The kits are a valuable teaching tool, whether the students are teens who are entirely new to engineering or structural engineering graduate students. The kits provide flexibility to allow the user to experiment and create various structures while maintaining structural accuracy. This hands-on approach is more accessible than computer modeling. It allows the student to experience the consequences of loads on their structure directly. Though, the kits are not for everyone. The small parts in a kit do not make it suitable for younger children, and the cost of a kit can be prohibitively expensive for some. However, overall, the kits are a helpful aid in training the next generation of structural engineers and in piquing students’ curiosity about structures and stability.■