[Hwang Min-ho Column] Becoming a Student Again in Order to Teach

[Hwang Min-ho Column] Hwang Min-ho, Teacher, Department of Industrial Machinery, Wonju Yeongseo High School

In my previous article, I said that even now, after going from a student learning agriculture to a teacher teaching agriculture, I become a student again in order to teach my students properly. Looking back, the reason I began challenging myself to earn various certifications and learn new skills after becoming a teacher ultimately started from that thought. After being appointed as a teacher in 2016, I took charge of agricultural machinery classes and agricultural machinery management work starting in the following year, 2017. I had more opportunities to handle actual agricultural machinery and various types of equipment, and the textbook also contained material related to operating forklifts. As I explained the structure and operation methods of equipment to students, ‘if I am to teach students about equipment, shouldn’t I, as their teacher, at least be able to operate it myself first?’ That thought came to mind. So I challenged myself to earn a forklift operator craftsman certificate and obtained the qualification in 2017. At the time, I did not think I would continue to earn certifications in many different fields. I simply thought that if it was a skill I had to teach students, I should try it myself first and understand it.
 

My students’ failures, the turning point that made me learn again

That same year, something happened that became an even bigger turning point for me. I was put in charge of guiding students taking the practical qualification test for those exempt from the written exam for the Agricultural Machinery Maintenance Craftsman certification. It was an exam students at our school took every year, and because I was also a teacher who had majored in agricultural machinery, I thought I would be able to guide them without much difficulty. To be honest, I think I took the exam too lightly. I was confident that most of my students would pass, but the results were different from what I expected. A large number of the students I had taught failed. The first feeling I had when I received the results was guilt. The students were the ones who failed the exam, but I was the one who had taught them.

Looking back, at the time I think I was relying to some extent on the fact that I had majored in agricultural machinery and passed the teacher appointment examination. Knowing the theory of agricultural machinery and being able to properly teach practical skills to students were different matters, but I did not fully understand that difference. Nor was there anyone who systematically taught me, a new teacher at the time, practical maintenance skills. But that could not be a reason to explain my students’ failure to pass. After all, I was the person who had to teach the students. At that moment, I engraved one promise in my heart. “Let me not forget this sense of regret I feel toward the first students I met. Let me never again allow a student’s potential to stop because I do not know something. For the students I meet from now on, let me first learn and master what I must, and teach them responsibly.” That promise later became the biggest reason I studied for various certifications and professional skills.

To teach students proper maintenance skills, I had to learn again myself first. Agricultural machinery is complex machinery in which the engine and power transmission system, hydraulic devices, the chassis, and various machine elements are connected and operate together. To understand this structure systematically, I raised the level of my studies, starting with the Construction Machinery Maintenance Craftsman certification and moving on to Agricultural Machinery Maintenance Craftsman, Agricultural Machinery Industrial Engineer, and even Construction Machinery Maintenance Industrial Engineer. While preparing for these qualifications, I disassembled and assembled engines and hydraulic devices, repeatedly used tools and measuring instruments, and relearned the structures and roles of fastening components and machine elements. My classes changed little by little as a result. Rather than only teaching the names of tools and the order in which to use them, I became able to explain more easily than before why a particular tool should be used, what to be careful about when fastening bolts and nuts, and what roles bearings and gears play in machinery. With hydraulics as well, I no longer stopped at having students memorize the names of pumps, valves, and cylinders; I became able to connect the explanation to actual devices, explaining what path hydraulic oil follows as it flows, where pressure is formed, and why the direction of cylinder movement changes depending on valve operation. I came to realize that the more deeply I understood the technology, the easier I could actually explain it to students.
 

Learning machines beyond the textbook

Agricultural machinery classes also required the ability to operate various types of equipment. When people think of agricultural machinery, they commonly think first of tractors, rice transplanters, and combine harvesters, but the range of mechanical technologies needed in actual agricultural settings is broader than that. Various tasks are carried out, such as transporting and stacking materials or excavating and leveling soil, and in the process of operating and maintaining agricultural machinery, technologies related to construction machinery are naturally connected. I thought that in order to properly teach students about the equipment that appears in textbooks and use it in the field, I first had to operate it myself and understand its characteristics. So, starting with forklifts, I obtained operating qualifications for various types of construction machinery, including excavators, loaders, cranes, rollers, drilling machines, bulldozers, and tower cranes.

The experience of operating them myself also helped in class. As I came to understand the different operating characteristics, working visibility, and movements of work devices for each piece of equipment, I was able to explain more specifically to students not only simple operating methods but also what to check and what to be careful about when working. I also learned that the skills needed by a teacher who teaches agricultural machinery are not confined only within the name “agricultural machinery”.
 

When I learned one thing, I saw another area where I was lacking

The more deeply I studied maintenance technology, the more I began to see other areas where I was lacking. Modern agricultural machinery is not composed only of mechanical devices. Electrical circuits, including starting circuits and charging circuits, are used, and various switches, relays, sensors, and signals are involved in the operation of machinery. There were cases where it was difficult to accurately identify the cause of a failure by understanding only the mechanical structure. So I challenged myself to earn an Electrician Craftsman certificate. By studying the basic principles of electrical circuits and electrical equipment, I gained a foundation for thinking separately about whether a machine’s abnormality was a mechanical problem, a power supply problem, or a circuit or signal problem. It also became even clearer to me that, for a teacher majoring in agricultural machinery, electricity is not a separate field but a technology that must be understood in order to understand modern agricultural machinery.

Welding, too, was naturally connected to maintenance. When agricultural machinery is used, bolts and nuts can break, or structures and major parts can be damaged. Not every problem can be solved only by replacing parts, and welding skills were necessary to repair damaged parts or fabricate needed structures. For these reasons, I obtained a Covered Arc Welding Craftsman certificate, and gained a foundation for teaching students even the repair and fabrication skills needed in the maintenance process.

As I studied operation and maintenance, electricity and welding, I also came to think that there was another area of expertise I absolutely had to acquire. It was safety. Classes that handle agricultural machinery and agricultural work sites contain a variety of risk factors. Because rotating parts, hydraulic devices, electrical facilities, high-temperature parts, and heavy objects are handled, and because various machines are operated directly, a small mistake can lead to a major accident. It was not enough simply to tell students to ‘be careful’. I wanted to explain, with grounds, what risk factors exist in which tasks, and what must be checked to prevent accidents. So I also challenged myself to earn the Agricultural Work Safety and Health Engineer qualification and obtained it. That is because I believed that teaching students to use skills safely is an important area of expertise a teacher must possess, just as much as teaching the skills well.

Looking back, the qualifications I obtained were not separate from one another. I learned operation in order to teach students about equipment, and I studied maintenance in order to properly understand machines. As I studied maintenance more deeply, I had to understand electricity, and I learned welding in order to repair machines and fabricate structures. And in order to teach all these skills safely to students, I even studied agricultural work safety. Learning one thing did not mean the learning was over; rather, it revealed another area of deficiency that lay beyond it.
 

After going round and round, back to agricultural machinery

As I studied various technologies in that way, I eventually returned to agricultural machinery, where I had first begun. ‘Then to what level do I actually understand agricultural machinery, my own major?’ This question became the reason I challenged myself to earn the Agricultural Machinery Engineer qualification. As a teacher who majored in agricultural machinery and teaches agricultural machinery to students, this was the one qualification I truly wanted to obtain. But as I prepared for the exam, the meaning of the Agricultural Machinery Engineer qualification grew beyond simply adding one more certificate.

In particular, it was meaningful that while preparing for the written-response exam, I studied machine element design and mechanics again. I once again encountered the subjects I had studied while preparing for the teacher appointment examination, such as work and force, power and speed, efficiency, shafts and gears. But even when studying the same material, my perspective after becoming a teacher was different. When preparing for the teacher appointment examination, solving the given problems and finding the correct answers were important, but now, while solving problems, I also found myself thinking ‘how should I explain this to students so they can understand it most easily?’. Rather than having students memorize power simply as a formula, I could explain why greater power is needed to perform a certain amount of work in a shorter time by connecting it to actual agricultural machinery operations, and I was able to teach speed and efficiency not as numbers in exam questions but in connection with the actual process by which power generated in the engine is transmitted to the implement. Formulas I had once memorized for the teacher appointment examination had now become a language for explaining the movement of machines to students.

The CAD design I learned while preparing for the practical exam for the Agricultural Machinery Engineer qualification also expanded the scope of my classes. Previously, I had studied mainly maintenance skills such as disassembling completed machines, finding faults, and repairing them, but as I learned CAD, I also studied design technology: thinking about the necessary structures, arranging machine elements, and representing them in drawings. I came to see machine elements such as shafts and bearings, bolts and nuts not merely as parts to be disassembled and assembled, but to think about why they were placed in those positions, and what kind of structure they should be designed with. This experience also helped when I taught students three-dimensional CAD programs such as Autodesk Inventor. As I became able not only to teach the program’s commands but also to explain together how actual machine elements and structures are modeled and designed, maintenance technology, which involves disassembling machines, finding faults, and repairing them, and design technology, which involves understanding machine elements and representing necessary structures in drawings, began to connect as one.

2024 was especially meaningful when I obtained the Agricultural Machinery Engineer qualification for this reason. I learned operation in order to teach students about equipment, and after experiencing my students’ failure to pass, I studied maintenance. While studying maintenance, I learned the need for electricity and welding, and I also studied agricultural work safety in order to guide students safely. And at the end of all that learning, I returned once again to my major, agricultural machinery. In that process, I learned not only how to operate agricultural machinery but also how to diagnose and maintain faults, and further, I was able to learn how to calculate machine elements and design structures. The fact that I have grown little by little into a teacher who can guide students in both the practical work of maintenance sites and the practical work of design sites is something I am proud of.
 

Certifications were a record of filling my deficiencies

Of course, having many certifications does not make someone a good teacher. Nor does obtaining one qualification mean that I have come to know everything about that field. Rather, the more I studied, the more I saw what I did not know. Even so, it was clear that when teaching something to students, I was becoming a teacher who could explain based not merely on conveying the textbook content as it was, but on my own experience of operating, disassembling, repairing, understanding circuits, calculating, and designing.

Looking back, the certifications I obtained are not simply a list of credentials. They are a record of learning through which I filled, one by one, the deficiencies I encountered while teaching students. At first, I began studying because I wanted to teach students even one more thing properly, but after learning one thing, another learning opportunity was waiting behind it. In that way, the studying I had begun in order to teach students was, before I knew it, helping me grow again.

And as I obtained certifications one by one and learned skills, another question began to remain in my mind. ‘Are the skills that allow one to obtain a qualification, and truly skilled technique, the same thing?’ Certifications confirmed what I knew and what I could do, but how accurately and deeply I had mastered those skills was another matter. That question led me outside the classroom again. The learning I had begun in order to teach was now heading toward the next path called ‘mastery’.