Good teachers are like good wine. They get better as you get older. José Manuel Macías was the director of the Zürich Schule when I was little. We all knew him as *señor Macías*.

He was an Industrial Engineer, and he taught *Mathematik* at our school, which was Mathematics in German (it was a one-hour per week lesson). Every week, he delivered us a one-page mathematical problem written in German, and we should solve it for the next week. The statement was tricky, and the problem was a trigonometrical one.

Usually, it started with:

Berechne d__ Fläche d__ schraffiert__ Figur.

He left some blanks on purpose for us to fill them up: *Berechne die Fläche der schraffierten Figur*. Under the statement, he drew a geometrical figure, and we should calculate its area. Then, he divided the page into two cells. We wrote the mathematical operations (*Berechnung*) on the left. Then we explained how we solved the problem (*Beschreibung*) on the right. Finally, at the bottom, we should write our answer in no more than two sentences (*Antwortsatz*).

Looking at his class now, I should say that it was beautiful. He made us think using a single page. And not only that, after that single week that we had to solve the problem, he came into the classroom with a microphone, and he randomly selected one of us to present our solution. He wrote number on a paper, and we got asked—one by one—to say a number between $1$ and $N$, where $N$ was the total number of students in that class. The winner had the privilege to do a performance. Everyone hated public speaking—especially at that young age. The teacher was the only one enjoying that lottery. 😅

We got a masterclass in maths, German, writing, and speaking—and in just one hour. Kids don't notice what adults do for us when we are little. Over the last few years, I've always thought that he was guilty of me becoming an engineer. I'm so grateful for it—the fear of public speaking hasn't gone although.

Teachers are so important: they build our future. A well-educated country is a wealthy country. So, kudos to all the teachers from that little school in Barcelona.

Hi, I'm Erik, an engineer from Barcelona. If you like the post or have any comments, say hi.