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Is there something in your past to put you on a path to become an educator? When I was a teenager I did one of those guidance counsellor tests which suggested I should become one. I laughed. But a couple of years later, when I helped a girl with her chemistry homework at the college library, she said I had the makings of a good teacher. My favorite chemistry professor in university reminded me of the Gilligan鈥檚 Island professor. Professor McElcheron was a tinkerer in his own lab, and instead of being shipwrecked like the TV character, he lived by choice on his own island. And he too thought I was the type who should teach something that matters鈥攖he science of matter, commonly known as chemistry.聽

In college, I found mathematics easier than chemistry, but when I taught the former it was difficult to routinely include activities that weren鈥檛 exclusively of the paper and pen variety. When I was finally given a load that included only chemistry courses, I breathed a sigh of relief. Finally my students and I didn鈥檛 have to hear my voice all period long! I could show them how to set up a campfire while explaining the roles of surface area, oxygen, heat and fuel. We鈥檇 balance the buoyancy force of hydrogen balloons with paper clips hanging from a string or suggest and demonstrate ways of exploding the balloons while varying the resulting color from red to colorless to green. I could watch students build electrochemical cells and then link them together in series to step up the voltage.聽

When you first teach chemistry, you discover that the order of topics is not fixed in stone. That is nice because you can come up with a sequence that suits your style. You also learn that 鈥渉ands-on鈥� activities are the best educational tools and luckily there are many excellent chemistry experiments that students can perform. But when it comes to texts, while there are several masterpiece introductory organic chemistry books, the same cannot be said for a high school or college freshman general chemistry text. It is still waiting to be written, perhaps by you! Publishers were on the right track in the 1960s with the Chem Study program, but afterwards they succumbed to inferior approaches.聽

The most important reason to teach chemistry is that society鈥檚 members should be exposed to all three of the fundamental sciences: physics, chemistry and biology. One can eat and cook well without going to school, but learning chemistry can give worthwhile insight into why a delicious brown crust on bread forms, why an apple with a bit of lemon juice doesn鈥檛 turn brown, and why most fad diets are destined to fail. On a sensual level, your students will still enjoy a perfume diffusing from their skin to their noses, but the experience will be intensified by an understanding of the chemistry involved. They鈥檒l recognize it as an example of Brownian motion. They鈥檒l learn that how fast the perfume鈥檚 key components reach their nose is inversely proportional to their densities. And the molecules can only signal their brains if they interact with the right combination of olfactory receptors.聽

Someone has to teach our youth that without the chemistry of chlorine and ozone, city tap water would be undrinkable. Without soap, doctors鈥� hands would be contaminated and without wires made of purified copper electricity would not flow. With a knowledge of chemistry, bad things have been done too, but corrections have been made, with more remedies on the horizon. Knowledge of chemistry is vital for a transition to a greener, more long-lasting economy and civilization.聽

Enrico Uva is a retired chemistry teacher who still enjoys learning chemistry, other sciences and mathematics.聽